Vulnerabilities

25 via 176 paths

Dependencies

473

Source

GitHub

Commit

2bfd20a2

Find, fix and prevent vulnerabilities in your code.

Severity
  • 1
  • 9
  • 14
  • 1
Status
  • 25
  • 0
  • 0

critical severity

Incomplete List of Disallowed Inputs

  • Vulnerable module: babel-traverse
  • Introduced through: babel-cli@6.26.0 and babel-preset-env@1.7.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-computed-properties@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-systemjs@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-helper-call-delegate@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-exponentiation-operator@6.24.1 babel-helper-builder-binary-assignment-operator-visitor@6.24.1 babel-helper-explode-assignable-expression@6.24.1 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0

Overview

Affected versions of this package are vulnerable to Incomplete List of Disallowed Inputs when using plugins that rely on the path.evaluate() or path.evaluateTruthy() internal Babel methods.

Note:

This is only exploitable if the attacker uses known affected plugins such as @babel/plugin-transform-runtime, @babel/preset-env when using its useBuiltIns option, and any "polyfill provider" plugin that depends on @babel/helper-define-polyfill-provider. No other plugins under the @babel/ namespace are impacted, but third-party plugins might be.

Users that only compile trusted code are not impacted.

Workaround

Users who are unable to upgrade the library can upgrade the affected plugins instead, to avoid triggering the vulnerable code path in affected @babel/traverse.

Remediation

There is no fixed version for babel-traverse.

References

high severity

Prototype Pollution

  • Vulnerable module: @grpc/grpc-js
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 @grpc/grpc-js@0.3.6
    Remediation: Upgrade to firebase-admin@8.0.0.

Overview

@grpc/grpc-js is a gRPC Library for Node

Affected versions of this package are vulnerable to Prototype Pollution via loadPackageDefinition.

POC:

const { loadPackageDefinition } = require('grpc');
loadPackageDefinition({'__proto__.polluted': true});
console.log(polluted);

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade @grpc/grpc-js to version 1.1.8 or higher.

References

high severity

Regular Expression Denial of Service (ReDoS)

  • Vulnerable module: ansi-regex
  • Introduced through: babel-cli@6.26.0, babel-preset-env@1.7.0 and others

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-computed-properties@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-systemjs@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-helper-call-delegate@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-block-scoping@6.26.0 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-computed-properties@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-systemjs@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-parameters@6.24.1 babel-helper-call-delegate@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-exponentiation-operator@6.24.1 babel-helper-builder-binary-assignment-operator-visitor@6.24.1 babel-helper-explode-assignable-expression@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-function-name@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-object-super@6.24.1 babel-helper-replace-supers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-exponentiation-operator@6.24.1 babel-helper-builder-binary-assignment-operator-visitor@6.24.1 babel-helper-explode-assignable-expression@6.24.1 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 has-ansi@2.0.0 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 babel-helpers@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-async-to-generator@6.24.1 babel-helper-remap-async-to-generator@6.24.1 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-classes@6.24.1 babel-helper-define-map@6.26.0 babel-helper-function-name@6.24.1 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 babel-plugin-transform-es2015-modules-umd@6.24.1 babel-plugin-transform-es2015-modules-amd@6.24.1 babel-plugin-transform-es2015-modules-commonjs@6.26.2 babel-template@6.26.0 babel-traverse@6.26.0 babel-code-frame@6.26.0 chalk@1.1.3 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 wrap-ansi@2.1.0 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 wrap-ansi@2.1.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 wrap-ansi@2.1.0 strip-ansi@3.0.1 ansi-regex@2.1.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 yargs@3.32.0 cliui@3.2.0 wrap-ansi@2.1.0 string-width@1.0.2 strip-ansi@3.0.1 ansi-regex@2.1.1

Overview

Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS) due to the sub-patterns [[\\]()#;?]* and (?:;[-a-zA-Z\\d\\/#&.:=?%@~_]*)*.

PoC

import ansiRegex from 'ansi-regex';

for(var i = 1; i <= 50000; i++) {
    var time = Date.now();
    var attack_str = "\u001B["+";".repeat(i*10000);
    ansiRegex().test(attack_str)
    var time_cost = Date.now() - time;
    console.log("attack_str.length: " + attack_str.length + ": " + time_cost+" ms")
}

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its original and legitimate users. There are many types of DoS attacks, ranging from trying to clog the network pipes to the system by generating a large volume of traffic from many machines (a Distributed Denial of Service - DDoS - attack) to sending crafted requests that cause a system to crash or take a disproportional amount of time to process.

The Regular expression Denial of Service (ReDoS) is a type of Denial of Service attack. Regular expressions are incredibly powerful, but they aren't very intuitive and can ultimately end up making it easy for attackers to take your site down.

Let’s take the following regular expression as an example:

regex = /A(B|C+)+D/

This regular expression accomplishes the following:

  • A The string must start with the letter 'A'
  • (B|C+)+ The string must then follow the letter A with either the letter 'B' or some number of occurrences of the letter 'C' (the + matches one or more times). The + at the end of this section states that we can look for one or more matches of this section.
  • D Finally, we ensure this section of the string ends with a 'D'

The expression would match inputs such as ABBD, ABCCCCD, ABCBCCCD and ACCCCCD

It most cases, it doesn't take very long for a regex engine to find a match:

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCD")'
0.04s user 0.01s system 95% cpu 0.052 total

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCX")'
1.79s user 0.02s system 99% cpu 1.812 total

The entire process of testing it against a 30 characters long string takes around ~52ms. But when given an invalid string, it takes nearly two seconds to complete the test, over ten times as long as it took to test a valid string. The dramatic difference is due to the way regular expressions get evaluated.

Most Regex engines will work very similarly (with minor differences). The engine will match the first possible way to accept the current character and proceed to the next one. If it then fails to match the next one, it will backtrack and see if there was another way to digest the previous character. If it goes too far down the rabbit hole only to find out the string doesn’t match in the end, and if many characters have multiple valid regex paths, the number of backtracking steps can become very large, resulting in what is known as catastrophic backtracking.

Let's look at how our expression runs into this problem, using a shorter string: "ACCCX". While it seems fairly straightforward, there are still four different ways that the engine could match those three C's:

  1. CCC
  2. CC+C
  3. C+CC
  4. C+C+C.

The engine has to try each of those combinations to see if any of them potentially match against the expression. When you combine that with the other steps the engine must take, we can use RegEx 101 debugger to see the engine has to take a total of 38 steps before it can determine the string doesn't match.

From there, the number of steps the engine must use to validate a string just continues to grow.

String Number of C's Number of steps
ACCCX 3 38
ACCCCX 4 71
ACCCCCX 5 136
ACCCCCCCCCCCCCCX 14 65,553

By the time the string includes 14 C's, the engine has to take over 65,000 steps just to see if the string is valid. These extreme situations can cause them to work very slowly (exponentially related to input size, as shown above), allowing an attacker to exploit this and can cause the service to excessively consume CPU, resulting in a Denial of Service.

Remediation

Upgrade ansi-regex to version 3.0.1, 4.1.1, 5.0.1, 6.0.1 or higher.

References

high severity
new

Uncontrolled resource consumption

  • Vulnerable module: braces
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 anymatch@1.3.2 micromatch@2.3.11 braces@1.8.5
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 braces@2.3.2

Overview

braces is a Bash-like brace expansion, implemented in JavaScript.

Affected versions of this package are vulnerable to Uncontrolled resource consumption due improper limitation of the number of characters it can handle, through the parse function. An attacker can cause the application to allocate excessive memory and potentially crash by sending imbalanced braces as input.

PoC

const { braces } = require('micromatch');

console.log("Executing payloads...");

const maxRepeats = 10;

for (let repeats = 1; repeats <= maxRepeats; repeats += 1) {
  const payload = '{'.repeat(repeats*90000);

  console.log(`Testing with ${repeats} repeats...`);
  const startTime = Date.now();
  braces(payload);
  const endTime = Date.now();
  const executionTime = endTime - startTime;
  console.log(`Regex executed in ${executionTime / 1000}s.\n`);
} 

Remediation

Upgrade braces to version 3.0.3 or higher.

References

high severity

Denial of Service (DoS)

  • Vulnerable module: dicer
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 dicer@0.3.1

Overview

Affected versions of this package are vulnerable to Denial of Service (DoS). A malicious attacker can send a modified form to server, and crash the nodejs service. An attacker could sent the payload again and again so that the service continuously crashes.

PoC:

    fetch('form-image', {
      method: 'POST',
      headers: {
        ['content-type']: 'multipart/form-data; boundary=----WebKitFormBoundaryoo6vortfDzBsDiro',
        ['content-length']: '145',
        host: '127.0.0.1:8000',
        connection: 'keep-alive',
      },
      body: '------WebKitFormBoundaryoo6vortfDzBsDiro\r\n Content-Disposition: form-data; name="bildbeschreibung"\r\n\r\n\r\n------WebKitFormBoundaryoo6vortfDzBsDiro--'
    });

Remediation

There is no fixed version for dicer.

References

high severity

Prototype Pollution

  • Vulnerable module: json-bigint
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gcp-metadata@1.0.0 json-bigint@0.3.1
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gcp-metadata@1.0.0 json-bigint@0.3.1
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gcp-metadata@1.0.0 json-bigint@0.3.1
    Remediation: Upgrade to firebase-admin@9.0.0.

Overview

json-bigint is a JSON.parse with bigints support

Affected versions of this package are vulnerable to Prototype Pollution via the parse function.

POC

const JSONbig = require('json-bigint')
const json = '{"__proto__":1000000000000000,"c":{"__proto__":[],"length":1e200}}'
const r = JSONbig.parse(json)
console.log(r.toString())

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade json-bigint to version 1.0.0 or higher.

References

high severity
new

Inefficient Regular Expression Complexity

  • Vulnerable module: micromatch
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 anymatch@1.3.2 micromatch@2.3.11
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10

Overview

Affected versions of this package are vulnerable to Inefficient Regular Expression Complexity due to the use of unsafe pattern configurations that allow greedy matching through the micromatch.braces() function. An attacker can cause the application to hang or slow down by passing a malicious payload that triggers extensive backtracking in regular expression processing.

Remediation

Upgrade micromatch to version 4.0.6 or higher.

References

high severity

Prototype Pollution

  • Vulnerable module: unset-value
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 snapdragon@0.8.2 base@0.11.2 cache-base@1.0.1 unset-value@1.0.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 braces@2.3.2 snapdragon@0.8.2 base@0.11.2 cache-base@1.0.1 unset-value@1.0.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 extglob@2.0.4 snapdragon@0.8.2 base@0.11.2 cache-base@1.0.1 unset-value@1.0.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 nanomatch@1.2.13 snapdragon@0.8.2 base@0.11.2 cache-base@1.0.1 unset-value@1.0.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 readdirp@2.2.1 micromatch@3.1.10 extglob@2.0.4 expand-brackets@2.1.4 snapdragon@0.8.2 base@0.11.2 cache-base@1.0.1 unset-value@1.0.0

Overview

Affected versions of this package are vulnerable to Prototype Pollution via the unset function in index.js, because it allows access to object prototype properties.

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade unset-value to version 2.0.1 or higher.

References

high severity

Improper Verification of Cryptographic Signature

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@10.0.2.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature due to RSA's PKCS#1 v1.5 signature verification code which does not check for tailing garbage bytes after decoding a DigestInfo ASN.1 structure. This can allow padding bytes to be removed and garbage data added to forge a signature when a low public exponent is being used.

Remediation

Upgrade node-forge to version 1.3.0 or higher.

References

high severity

Prototype Pollution

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@9.2.0.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Prototype Pollution via the util.setPath function.

Note: version 0.10.0 is a breaking change removing the vulnerable functions.

POC:

const nodeforge = require('node-forge');
var obj = {};
nodeforge.util.setPath(obj, ['__proto__', 'polluted'], true);
console.log(polluted);

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade node-forge to version 0.10.0 or higher.

References

medium severity

Use of a Broken or Risky Cryptographic Algorithm

  • Vulnerable module: jsonwebtoken
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 jsonwebtoken@8.1.0
    Remediation: Upgrade to firebase-admin@11.4.1.

Overview

jsonwebtoken is a JSON Web Token implementation (symmetric and asymmetric)

Affected versions of this package are vulnerable to Use of a Broken or Risky Cryptographic Algorithm such that the library can be misconfigured to use legacy, insecure key types for signature verification. For example, DSA keys could be used with the RS256 algorithm.

Exploitability

Users are affected when using an algorithm and a key type other than the combinations mentioned below:

EC: ES256, ES384, ES512

RSA: RS256, RS384, RS512, PS256, PS384, PS512

RSA-PSS: PS256, PS384, PS512

And for Elliptic Curve algorithms:

ES256: prime256v1

ES384: secp384r1

ES512: secp521r1

Workaround

Users who are unable to upgrade to the fixed version can use the allowInvalidAsymmetricKeyTypes option to true in the sign() and verify() functions to continue usage of invalid key type/algorithm combination in 9.0.0 for legacy compatibility.

Remediation

Upgrade jsonwebtoken to version 9.0.0 or higher.

References

medium severity

Improper Restriction of Security Token Assignment

  • Vulnerable module: jsonwebtoken
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 jsonwebtoken@8.1.0
    Remediation: Upgrade to firebase-admin@11.4.1.

Overview

jsonwebtoken is a JSON Web Token implementation (symmetric and asymmetric)

Affected versions of this package are vulnerable to Improper Restriction of Security Token Assignment via the secretOrPublicKey argument due to misconfigurations of the key retrieval function jwt.verify(). Exploiting this vulnerability might result in incorrect verification of forged tokens when tokens signed with an asymmetric public key could be verified with a symmetric HS256 algorithm.

Note: This vulnerability affects your application if it supports the usage of both symmetric and asymmetric keys in jwt.verify() implementation with the same key retrieval function.

Remediation

Upgrade jsonwebtoken to version 9.0.0 or higher.

References

medium severity

Prototype Pollution

  • Vulnerable module: json5
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-core@6.26.3 json5@0.5.1
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 babel-register@6.26.0 babel-core@6.26.3 json5@0.5.1

Overview

Affected versions of this package are vulnerable to Prototype Pollution via the parse method , which does not restrict parsing of keys named __proto__, allowing specially crafted strings to pollute the prototype of the resulting object. This pollutes the prototype of the object returned by JSON5.parse and not the global Object prototype (which is the commonly understood definition of Prototype Pollution). Therefore, the actual impact will depend on how applications utilize the returned object and how they filter unwanted keys.

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade json5 to version 1.0.2, 2.2.2 or higher.

References

medium severity

Improper Authentication

  • Vulnerable module: jsonwebtoken
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 jsonwebtoken@8.1.0
    Remediation: Upgrade to firebase-admin@11.4.1.

Overview

jsonwebtoken is a JSON Web Token implementation (symmetric and asymmetric)

Affected versions of this package are vulnerable to Improper Authentication such that the lack of algorithm definition in the jwt.verify() function can lead to signature validation bypass due to defaulting to the none algorithm for signature verification.

Exploitability

Users are affected only if all of the following conditions are true for the jwt.verify() function:

  1. A token with no signature is received.

  2. No algorithms are specified.

  3. A falsy (e.g., null, false, undefined) secret or key is passed.

Remediation

Upgrade jsonwebtoken to version 9.0.0 or higher.

References

medium severity

Prototype Pollution

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@10.0.2.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Prototype Pollution via the forge.debug API if called with untrusted input.

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade node-forge to version 1.0.0 or higher.

References

medium severity

Missing Release of Resource after Effective Lifetime

  • Vulnerable module: inflight
  • Introduced through: babel-cli@6.26.0 and firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 glob@7.2.3 inflight@1.0.6
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 protobufjs@5.0.3 glob@7.2.3 inflight@1.0.6
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc@1.24.11 @mapbox/node-pre-gyp@1.0.11 rimraf@3.0.2 glob@7.2.3 inflight@1.0.6
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 protobufjs@5.0.3 glob@7.2.3 inflight@1.0.6
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 grpc-gcp@0.1.1 grpc@1.24.11 @mapbox/node-pre-gyp@1.0.11 rimraf@3.0.2 glob@7.2.3 inflight@1.0.6

Overview

Affected versions of this package are vulnerable to Missing Release of Resource after Effective Lifetime via the makeres function due to improperly deleting keys from the reqs object after execution of callbacks. This behavior causes the keys to remain in the reqs object, which leads to resource exhaustion.

Exploiting this vulnerability results in crashing the node process or in the application crash.

Note: This library is not maintained, and currently, there is no fix for this issue. To overcome this vulnerability, several dependent packages have eliminated the use of this library.

To trigger the memory leak, an attacker would need to have the ability to execute or influence the asynchronous operations that use the inflight module within the application. This typically requires access to the internal workings of the server or application, which is not commonly exposed to remote users. Therefore, “Attack vector” is marked as “Local”.

PoC

const inflight = require('inflight');

function testInflight() {
  let i = 0;
  function scheduleNext() {
    let key = `key-${i++}`;
    const callback = () => {
    };
    for (let j = 0; j < 1000000; j++) {
      inflight(key, callback);
    }

    setImmediate(scheduleNext);
  }


  if (i % 100 === 0) {
    console.log(process.memoryUsage());
  }

  scheduleNext();
}

testInflight();

Remediation

There is no fixed version for inflight.

References

medium severity

Prototype Pollution

  • Vulnerable module: @firebase/util
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @firebase/app@0.3.17 @firebase/util@0.2.14
    Remediation: Upgrade to firebase-admin@8.3.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @firebase/database@0.3.20 @firebase/util@0.2.14
    Remediation: Upgrade to firebase-admin@9.4.2.

Overview

@firebase/util is a wrapper of some Webchannel Features for the Firebase JS SDK.

Affected versions of this package are vulnerable to Prototype Pollution. This vulnerability relates to the deepExtend function within the DeepCopy.ts file. Depending on if user input is provided, an attacker can overwrite and pollute the object prototype of a program.

PoC

const util = require('@firebase/util');
var payload = JSON.parse('{"__proto__": {"polluted": "vulnerable"}}');

const a = {
    nest: {
      number: 1,
      string: '1',
      object: { key: '1' },
      date: new Date(1),
      nest: {
        a: 1
      }
    },
  };

var result = util.deepExtend(a,payload);
console.log({}.polluted);

Details

Prototype Pollution is a vulnerability affecting JavaScript. Prototype Pollution refers to the ability to inject properties into existing JavaScript language construct prototypes, such as objects. JavaScript allows all Object attributes to be altered, including their magical attributes such as __proto__, constructor and prototype. An attacker manipulates these attributes to overwrite, or pollute, a JavaScript application object prototype of the base object by injecting other values. Properties on the Object.prototype are then inherited by all the JavaScript objects through the prototype chain. When that happens, this leads to either denial of service by triggering JavaScript exceptions, or it tampers with the application source code to force the code path that the attacker injects, thereby leading to remote code execution.

There are two main ways in which the pollution of prototypes occurs:

  • Unsafe Object recursive merge

  • Property definition by path

Unsafe Object recursive merge

The logic of a vulnerable recursive merge function follows the following high-level model:

merge (target, source)

  foreach property of source

    if property exists and is an object on both the target and the source

      merge(target[property], source[property])

    else

      target[property] = source[property]

When the source object contains a property named __proto__ defined with Object.defineProperty() , the condition that checks if the property exists and is an object on both the target and the source passes and the merge recurses with the target, being the prototype of Object and the source of Object as defined by the attacker. Properties are then copied on the Object prototype.

Clone operations are a special sub-class of unsafe recursive merges, which occur when a recursive merge is conducted on an empty object: merge({},source).

lodash and Hoek are examples of libraries susceptible to recursive merge attacks.

Property definition by path

There are a few JavaScript libraries that use an API to define property values on an object based on a given path. The function that is generally affected contains this signature: theFunction(object, path, value)

If the attacker can control the value of “path”, they can set this value to __proto__.myValue. myValue is then assigned to the prototype of the class of the object.

Types of attacks

There are a few methods by which Prototype Pollution can be manipulated:

Type Origin Short description
Denial of service (DoS) Client This is the most likely attack.
DoS occurs when Object holds generic functions that are implicitly called for various operations (for example, toString and valueOf).
The attacker pollutes Object.prototype.someattr and alters its state to an unexpected value such as Int or Object. In this case, the code fails and is likely to cause a denial of service.
For example: if an attacker pollutes Object.prototype.toString by defining it as an integer, if the codebase at any point was reliant on someobject.toString() it would fail.
Remote Code Execution Client Remote code execution is generally only possible in cases where the codebase evaluates a specific attribute of an object, and then executes that evaluation.
For example: eval(someobject.someattr). In this case, if the attacker pollutes Object.prototype.someattr they are likely to be able to leverage this in order to execute code.
Property Injection Client The attacker pollutes properties that the codebase relies on for their informative value, including security properties such as cookies or tokens.
For example: if a codebase checks privileges for someuser.isAdmin, then when the attacker pollutes Object.prototype.isAdmin and sets it to equal true, they can then achieve admin privileges.

Affected environments

The following environments are susceptible to a Prototype Pollution attack:

  • Application server

  • Web server

  • Web browser

How to prevent

  1. Freeze the prototype— use Object.freeze (Object.prototype).

  2. Require schema validation of JSON input.

  3. Avoid using unsafe recursive merge functions.

  4. Consider using objects without prototypes (for example, Object.create(null)), breaking the prototype chain and preventing pollution.

  5. As a best practice use Map instead of Object.

For more information on this vulnerability type:

Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018

Remediation

Upgrade @firebase/util to version 0.3.4 or higher.

References

medium severity

Improper Verification of Cryptographic Signature

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@10.0.2.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature due to RSA's PKCS#1 v1.5 signature verification code which does not properly check DigestInfo for a proper ASN.1 structure. This can lead to successful verification with signatures that contain invalid structures but a valid digest.

Remediation

Upgrade node-forge to version 1.3.0 or higher.

References

medium severity

Improper Verification of Cryptographic Signature

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@10.0.2.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature due to RSAs PKCS#1` v1.5 signature verification code which is lenient in checking the digest algorithm structure. This can allow a crafted structure that steals padding bytes and uses unchecked portion of the PKCS#1 encoded message to forge a signature when a low public exponent is being used.

Remediation

Upgrade node-forge to version 1.3.0 or higher.

References

medium severity

Regular Expression Denial of Service (ReDoS)

  • Vulnerable module: browserslist
  • Introduced through: babel-preset-env@1.7.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-preset-env@1.7.0 browserslist@3.2.8

Overview

browserslist is a Share target browsers between different front-end tools, like Autoprefixer, Stylelint and babel-env-preset

Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS) during parsing of queries.

PoC by Yeting Li

var browserslist = require("browserslist")
function build_attack(n) {
    var ret = "> "
    for (var i = 0; i < n; i++) {
        ret += "1"
    }
    return ret + "!";
}

// browserslist('> 1%')

//browserslist(build_attack(500000))
for(var i = 1; i <= 500000; i++) {
    if (i % 1000 == 0) {
        var time = Date.now();
        var attack_str = build_attack(i)
        try{
            browserslist(attack_str);
            var time_cost = Date.now() - time;
            console.log("attack_str.length: " + attack_str.length + ": " + time_cost+" ms");
            }
        catch(e){
        var time_cost = Date.now() - time;
        console.log("attack_str.length: " + attack_str.length + ": " + time_cost+" ms");
        }
    }
}

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its original and legitimate users. There are many types of DoS attacks, ranging from trying to clog the network pipes to the system by generating a large volume of traffic from many machines (a Distributed Denial of Service - DDoS - attack) to sending crafted requests that cause a system to crash or take a disproportional amount of time to process.

The Regular expression Denial of Service (ReDoS) is a type of Denial of Service attack. Regular expressions are incredibly powerful, but they aren't very intuitive and can ultimately end up making it easy for attackers to take your site down.

Let’s take the following regular expression as an example:

regex = /A(B|C+)+D/

This regular expression accomplishes the following:

  • A The string must start with the letter 'A'
  • (B|C+)+ The string must then follow the letter A with either the letter 'B' or some number of occurrences of the letter 'C' (the + matches one or more times). The + at the end of this section states that we can look for one or more matches of this section.
  • D Finally, we ensure this section of the string ends with a 'D'

The expression would match inputs such as ABBD, ABCCCCD, ABCBCCCD and ACCCCCD

It most cases, it doesn't take very long for a regex engine to find a match:

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCD")'
0.04s user 0.01s system 95% cpu 0.052 total

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCX")'
1.79s user 0.02s system 99% cpu 1.812 total

The entire process of testing it against a 30 characters long string takes around ~52ms. But when given an invalid string, it takes nearly two seconds to complete the test, over ten times as long as it took to test a valid string. The dramatic difference is due to the way regular expressions get evaluated.

Most Regex engines will work very similarly (with minor differences). The engine will match the first possible way to accept the current character and proceed to the next one. If it then fails to match the next one, it will backtrack and see if there was another way to digest the previous character. If it goes too far down the rabbit hole only to find out the string doesn’t match in the end, and if many characters have multiple valid regex paths, the number of backtracking steps can become very large, resulting in what is known as catastrophic backtracking.

Let's look at how our expression runs into this problem, using a shorter string: "ACCCX". While it seems fairly straightforward, there are still four different ways that the engine could match those three C's:

  1. CCC
  2. CC+C
  3. C+CC
  4. C+C+C.

The engine has to try each of those combinations to see if any of them potentially match against the expression. When you combine that with the other steps the engine must take, we can use RegEx 101 debugger to see the engine has to take a total of 38 steps before it can determine the string doesn't match.

From there, the number of steps the engine must use to validate a string just continues to grow.

String Number of C's Number of steps
ACCCX 3 38
ACCCCX 4 71
ACCCCCX 5 136
ACCCCCCCCCCCCCCX 14 65,553

By the time the string includes 14 C's, the engine has to take over 65,000 steps just to see if the string is valid. These extreme situations can cause them to work very slowly (exponentially related to input size, as shown above), allowing an attacker to exploit this and can cause the service to excessively consume CPU, resulting in a Denial of Service.

Remediation

Upgrade browserslist to version 4.16.5 or higher.

References

medium severity

Regular Expression Denial of Service (ReDoS)

  • Vulnerable module: date-and-time
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 date-and-time@0.6.3
    Remediation: Upgrade to firebase-admin@8.8.0.

Overview

date-and-time is an A Minimalist DateTime utility for Node.js and the browser

Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS) via date.compile.

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its original and legitimate users. There are many types of DoS attacks, ranging from trying to clog the network pipes to the system by generating a large volume of traffic from many machines (a Distributed Denial of Service - DDoS - attack) to sending crafted requests that cause a system to crash or take a disproportional amount of time to process.

The Regular expression Denial of Service (ReDoS) is a type of Denial of Service attack. Regular expressions are incredibly powerful, but they aren't very intuitive and can ultimately end up making it easy for attackers to take your site down.

Let’s take the following regular expression as an example:

regex = /A(B|C+)+D/

This regular expression accomplishes the following:

  • A The string must start with the letter 'A'
  • (B|C+)+ The string must then follow the letter A with either the letter 'B' or some number of occurrences of the letter 'C' (the + matches one or more times). The + at the end of this section states that we can look for one or more matches of this section.
  • D Finally, we ensure this section of the string ends with a 'D'

The expression would match inputs such as ABBD, ABCCCCD, ABCBCCCD and ACCCCCD

It most cases, it doesn't take very long for a regex engine to find a match:

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCD")'
0.04s user 0.01s system 95% cpu 0.052 total

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCX")'
1.79s user 0.02s system 99% cpu 1.812 total

The entire process of testing it against a 30 characters long string takes around ~52ms. But when given an invalid string, it takes nearly two seconds to complete the test, over ten times as long as it took to test a valid string. The dramatic difference is due to the way regular expressions get evaluated.

Most Regex engines will work very similarly (with minor differences). The engine will match the first possible way to accept the current character and proceed to the next one. If it then fails to match the next one, it will backtrack and see if there was another way to digest the previous character. If it goes too far down the rabbit hole only to find out the string doesn’t match in the end, and if many characters have multiple valid regex paths, the number of backtracking steps can become very large, resulting in what is known as catastrophic backtracking.

Let's look at how our expression runs into this problem, using a shorter string: "ACCCX". While it seems fairly straightforward, there are still four different ways that the engine could match those three C's:

  1. CCC
  2. CC+C
  3. C+CC
  4. C+C+C.

The engine has to try each of those combinations to see if any of them potentially match against the expression. When you combine that with the other steps the engine must take, we can use RegEx 101 debugger to see the engine has to take a total of 38 steps before it can determine the string doesn't match.

From there, the number of steps the engine must use to validate a string just continues to grow.

String Number of C's Number of steps
ACCCX 3 38
ACCCCX 4 71
ACCCCCX 5 136
ACCCCCCCCCCCCCCX 14 65,553

By the time the string includes 14 C's, the engine has to take over 65,000 steps just to see if the string is valid. These extreme situations can cause them to work very slowly (exponentially related to input size, as shown above), allowing an attacker to exploit this and can cause the service to excessively consume CPU, resulting in a Denial of Service.

Remediation

Upgrade date-and-time to version 0.14.2 or higher.

References

medium severity

Regular Expression Denial of Service (ReDoS)

  • Vulnerable module: glob-parent
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 glob-parent@2.0.0
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 anymatch@1.3.2 micromatch@2.3.11 parse-glob@3.0.4 glob-base@0.3.0 glob-parent@2.0.0

Overview

glob-parent is a package that helps extracting the non-magic parent path from a glob string.

Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS). The enclosure regex used to check for strings ending in enclosure containing path separator.

PoC by Yeting Li

var globParent = require("glob-parent")
function build_attack(n) {
var ret = "{"
for (var i = 0; i < n; i++) {
ret += "/"
}

return ret;
}

globParent(build_attack(5000));

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its original and legitimate users. There are many types of DoS attacks, ranging from trying to clog the network pipes to the system by generating a large volume of traffic from many machines (a Distributed Denial of Service - DDoS - attack) to sending crafted requests that cause a system to crash or take a disproportional amount of time to process.

The Regular expression Denial of Service (ReDoS) is a type of Denial of Service attack. Regular expressions are incredibly powerful, but they aren't very intuitive and can ultimately end up making it easy for attackers to take your site down.

Let’s take the following regular expression as an example:

regex = /A(B|C+)+D/

This regular expression accomplishes the following:

  • A The string must start with the letter 'A'
  • (B|C+)+ The string must then follow the letter A with either the letter 'B' or some number of occurrences of the letter 'C' (the + matches one or more times). The + at the end of this section states that we can look for one or more matches of this section.
  • D Finally, we ensure this section of the string ends with a 'D'

The expression would match inputs such as ABBD, ABCCCCD, ABCBCCCD and ACCCCCD

It most cases, it doesn't take very long for a regex engine to find a match:

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCD")'
0.04s user 0.01s system 95% cpu 0.052 total

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCX")'
1.79s user 0.02s system 99% cpu 1.812 total

The entire process of testing it against a 30 characters long string takes around ~52ms. But when given an invalid string, it takes nearly two seconds to complete the test, over ten times as long as it took to test a valid string. The dramatic difference is due to the way regular expressions get evaluated.

Most Regex engines will work very similarly (with minor differences). The engine will match the first possible way to accept the current character and proceed to the next one. If it then fails to match the next one, it will backtrack and see if there was another way to digest the previous character. If it goes too far down the rabbit hole only to find out the string doesn’t match in the end, and if many characters have multiple valid regex paths, the number of backtracking steps can become very large, resulting in what is known as catastrophic backtracking.

Let's look at how our expression runs into this problem, using a shorter string: "ACCCX". While it seems fairly straightforward, there are still four different ways that the engine could match those three C's:

  1. CCC
  2. CC+C
  3. C+CC
  4. C+C+C.

The engine has to try each of those combinations to see if any of them potentially match against the expression. When you combine that with the other steps the engine must take, we can use RegEx 101 debugger to see the engine has to take a total of 38 steps before it can determine the string doesn't match.

From there, the number of steps the engine must use to validate a string just continues to grow.

String Number of C's Number of steps
ACCCX 3 38
ACCCCX 4 71
ACCCCCX 5 136
ACCCCCCCCCCCCCCX 14 65,553

By the time the string includes 14 C's, the engine has to take over 65,000 steps just to see if the string is valid. These extreme situations can cause them to work very slowly (exponentially related to input size, as shown above), allowing an attacker to exploit this and can cause the service to excessively consume CPU, resulting in a Denial of Service.

Remediation

Upgrade glob-parent to version 5.1.2 or higher.

References

medium severity

Open Redirect

  • Vulnerable module: node-forge
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0 google-gax@0.25.6 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 @google-cloud/common@0.32.1 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/storage@2.5.0 gcs-resumable-upload@1.1.0 google-auth-library@3.1.2 gtoken@2.3.3 google-p12-pem@1.0.5 node-forge@0.10.0
    Remediation: Upgrade to firebase-admin@9.0.0.
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 node-forge@0.7.4
    Remediation: Upgrade to firebase-admin@10.0.2.

Overview

node-forge is a JavaScript implementations of network transports, cryptography, ciphers, PKI, message digests, and various utilities.

Affected versions of this package are vulnerable to Open Redirect via parseUrl function when it mishandles certain uses of backslash such as https:/\/\/\ and interprets the URI as a relative path.

PoC:


// poc.js
var forge = require("node-forge");
var url = forge.util.parseUrl("https:/\/\/\www.github.com/foo/bar");
console.log(url);

// Output of node poc.js:

{
  full: 'https://',
  scheme: 'https',
  host: '',
  port: 443,
  path: '/www.github.com/foo/bar',                        <<<---- path  should be "/foo/bar"
  fullHost: ''
}

Remediation

Upgrade node-forge to version 1.0.0 or higher.

References

medium severity

Insecure Storage of Sensitive Information

  • Vulnerable module: @google-cloud/firestore
  • Introduced through: firebase-admin@7.4.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c firebase-admin@7.4.0 @google-cloud/firestore@1.3.0
    Remediation: Upgrade to firebase-admin@11.1.0.

Overview

@google-cloud/firestore is a Firestore Client Library for Node.js

Affected versions of this package are vulnerable to Insecure Storage of Sensitive Information. An attacker with logs read access can potentially read sensitive information exposed by developers that log objects through this._settings, which could inadvertently log the firestore key.

Remediation

Upgrade @google-cloud/firestore to version 6.2.0 or higher.

References

low severity

Regular Expression Denial of Service (ReDoS)

  • Vulnerable module: braces
  • Introduced through: babel-cli@6.26.0

Detailed paths

  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 anymatch@1.3.2 micromatch@2.3.11 braces@1.8.5
  • Introduced through: firestore-backup@steadyequipment/node-firestore-backup#2bfd20a28ed4ed49c2db478bbce9ecba3d4a0f3c babel-cli@6.26.0 chokidar@1.7.0 anymatch@1.3.2 micromatch@2.3.11 braces@1.8.5

Overview

braces is a Bash-like brace expansion, implemented in JavaScript.

Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS). It used a regular expression (^\{(,+(?:(\{,+\})*),*|,*(?:(\{,+\})*),+)\}) in order to detects empty braces. This can cause an impact of about 10 seconds matching time for data 50K characters long.

Disclosure Timeline

  • Feb 15th, 2018 - Initial Disclosure to package owner
  • Feb 16th, 2018 - Initial Response from package owner
  • Feb 18th, 2018 - Fix issued
  • Feb 19th, 2018 - Vulnerability published

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its original and legitimate users. There are many types of DoS attacks, ranging from trying to clog the network pipes to the system by generating a large volume of traffic from many machines (a Distributed Denial of Service - DDoS - attack) to sending crafted requests that cause a system to crash or take a disproportional amount of time to process.

The Regular expression Denial of Service (ReDoS) is a type of Denial of Service attack. Regular expressions are incredibly powerful, but they aren't very intuitive and can ultimately end up making it easy for attackers to take your site down.

Let’s take the following regular expression as an example:

regex = /A(B|C+)+D/

This regular expression accomplishes the following:

  • A The string must start with the letter 'A'
  • (B|C+)+ The string must then follow the letter A with either the letter 'B' or some number of occurrences of the letter 'C' (the + matches one or more times). The + at the end of this section states that we can look for one or more matches of this section.
  • D Finally, we ensure this section of the string ends with a 'D'

The expression would match inputs such as ABBD, ABCCCCD, ABCBCCCD and ACCCCCD

It most cases, it doesn't take very long for a regex engine to find a match:

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCD")'
0.04s user 0.01s system 95% cpu 0.052 total

$ time node -e '/A(B|C+)+D/.test("ACCCCCCCCCCCCCCCCCCCCCCCCCCCCX")'
1.79s user 0.02s system 99% cpu 1.812 total

The entire process of testing it against a 30 characters long string takes around ~52ms. But when given an invalid string, it takes nearly two seconds to complete the test, over ten times as long as it took to test a valid string. The dramatic difference is due to the way regular expressions get evaluated.

Most Regex engines will work very similarly (with minor differences). The engine will match the first possible way to accept the current character and proceed to the next one. If it then fails to match the next one, it will backtrack and see if there was another way to digest the previous character. If it goes too far down the rabbit hole only to find out the string doesn’t match in the end, and if many characters have multiple valid regex paths, the number of backtracking steps can become very large, resulting in what is known as catastrophic backtracking.

Let's look at how our expression runs into this problem, using a shorter string: "ACCCX". While it seems fairly straightforward, there are still four different ways that the engine could match those three C's:

  1. CCC
  2. CC+C
  3. C+CC
  4. C+C+C.

The engine has to try each of those combinations to see if any of them potentially match against the expression. When you combine that with the other steps the engine must take, we can use RegEx 101 debugger to see the engine has to take a total of 38 steps before it can determine the string doesn't match.

From there, the number of steps the engine must use to validate a string just continues to grow.

String Number of C's Number of steps
ACCCX 3 38
ACCCCX 4 71
ACCCCCX 5 136
ACCCCCCCCCCCCCCX 14 65,553

By the time the string includes 14 C's, the engine has to take over 65,000 steps just to see if the string is valid. These extreme situations can cause them to work very slowly (exponentially related to input size, as shown above), allowing an attacker to exploit this and can cause the service to excessively consume CPU, resulting in a Denial of Service.

Remediation

Upgrade braces to version 2.3.1 or higher.

References