Find, fix and prevent vulnerabilities in your code.
critical severity
- Vulnerable module: xmldom
- Introduced through: pdf2table@0.0.1
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › pdf2table@0.0.1 › pdf2json@0.7.1 › xmldom@0.6.0
Overview
xmldom is an A pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module.
Affected versions of this package are vulnerable to Improper Input Validation due to parsing XML that is not well-formed, and contains multiple top-level elements. All the root nodes are being added to the childNodes
collection of the Document
, without reporting or throwing any error.
Workarounds
One of the following approaches might help, depending on your use case:
Instead of searching for elements in the whole DOM, only search in the
documentElement
.Reject a document with a document that has more than 1
childNode
.
PoC
var DOMParser = require('xmldom').DOMParser;
var xmlData = '<?xml version="1.0" encoding="UTF-8"?>\n' +
'<root>\n' +
' <branch girth="large">\n' +
' <leaf color="green" />\n' +
' </branch>\n' +
'</root>\n' +
'<root>\n' +
' <branch girth="twig">\n' +
' <leaf color="gold" />\n' +
' </branch>\n' +
'</root>\n';
var xmlDOM = new DOMParser().parseFromString(xmlData);
console.log(xmlDOM.toString());
This will result with the following output:
<?xml version="1.0" encoding="UTF-8"?><root>
<branch girth="large">
<leaf color="green"/>
</branch>
</root>
<root>
<branch girth="twig">
<leaf color="gold"/>
</branch>
</root>
Remediation
There is no fixed version for xmldom
.
References
critical severity
- Vulnerable module: sharp
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4Remediation: Upgrade to gulp-favicons@4.0.0.
Overview
sharp is a High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP, GIF, AVIF and TIFF images
Affected versions of this package are vulnerable to Heap-based Buffer Overflow when the ReadHuffmanCodes()
function is used. An attacker can craft a special WebP
lossless file that triggers the ReadHuffmanCodes()
function to allocate the HuffmanCode buffer with a size that comes from an array of precomputed sizes: kTableSize
. The color_cache_bits
value defines which size to use. The kTableSize
array only takes into account sizes for 8-bit first-level table lookups but not second-level table lookups. libwebp allows codes that are up to 15-bit (MAX_ALLOWED_CODE_LENGTH
). When BuildHuffmanTable() attempts to fill the second-level tables it may write data out-of-bounds. The OOB write to the undersized array happens in ReplicateValue.
Notes:
This is only exploitable if the color_cache_bits
value defines which size to use.
This vulnerability was also published on libwebp CVE-2023-5129
Changelog:
2023-09-12: Initial advisory publication
2023-09-27: Advisory details updated, including CVSS, references
2023-09-27: CVE-2023-5129 rejected as a duplicate of CVE-2023-4863
2023-09-28: Research and addition of additional affected libraries
2024-01-28: Additional fix information
Remediation
Upgrade sharp
to version 0.32.6 or higher.
References
high severity
- Vulnerable module: xmldom
- Introduced through: pdf2table@0.0.1
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › pdf2table@0.0.1 › pdf2json@0.7.1 › xmldom@0.6.0
Overview
xmldom is an A pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module.
Affected versions of this package are vulnerable to Prototype Pollution through the copy()
function in dom.js
. Exploiting this vulnerability is possible via the p
variable.
DISPUTED This vulnerability has been disputed by the maintainers of the package. Currently the only viable exploit that has been demonstrated is to pollute the target object (rather then the global object which is generally the case for Prototype Pollution vulnerabilities) and it is yet unclear if this limited attack vector exposes any vulnerability in the context of this package.
See the linked GitHub Issue for full details on the discussion around the legitimacy and potential revocation of this vulnerability.
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 mergeProperty 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
Freeze the prototype— use
Object.freeze (Object.prototype)
.Require schema validation of JSON input.
Avoid using unsafe recursive merge functions.
Consider using objects without prototypes (for example,
Object.create(null)
), breaking the prototype chain and preventing pollution.As a best practice use
Map
instead ofObject
.
For more information on this vulnerability type:
Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018
Remediation
There is no fixed version for xmldom
.
References
high severity
- Vulnerable module: bson
- Introduced through: mongodb@2.2.36
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › mongodb@2.2.36 › mongodb-core@2.1.20 › bson@1.0.9Remediation: Upgrade to mongodb@3.1.3.
Overview
bson is a BSON Parser for node and browser.
Affected versions of this package are vulnerable to Internal Property Tampering. The package will ignore an unknown value for an object's _bsotype
, leading to cases where an object is serialized as a document rather than the intended BSON type.
NOTE: This vulnerability has also been identified as: CVE-2019-2391
Remediation
Upgrade bson
to version 1.1.4 or higher.
References
high severity
- Vulnerable module: bson
- Introduced through: mongodb@2.2.36
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › mongodb@2.2.36 › mongodb-core@2.1.20 › bson@1.0.9Remediation: Upgrade to mongodb@3.1.3.
Overview
bson is a BSON Parser for node and browser.
Affected versions of this package are vulnerable to Internal Property Tampering. The package will ignore an unknown value for an object's _bsotype
, leading to cases where an object is serialized as a document rather than the intended BSON type.
NOTE: This vulnerability has also been identified as: CVE-2020-7610
Remediation
Upgrade bson
to version 1.1.4 or higher.
References
high severity
- Vulnerable module: ansi-regex
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4 › npmlog@4.1.2 › gauge@2.7.4 › strip-ansi@3.0.1 › ansi-regex@2.1.1
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4 › npmlog@4.1.2 › gauge@2.7.4 › string-width@1.0.2 › strip-ansi@3.0.1 › ansi-regex@2.1.1
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4 › prebuild-install@5.3.6 › npmlog@4.1.2 › gauge@2.7.4 › strip-ansi@3.0.1 › ansi-regex@2.1.1Remediation: Upgrade to gulp-favicons@4.0.0.
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4 › prebuild-install@5.3.6 › npmlog@4.1.2 › gauge@2.7.4 › string-width@1.0.2 › strip-ansi@3.0.1 › ansi-regex@2.1.1Remediation: Upgrade to gulp-favicons@4.0.0.
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:
- CCC
- CC+C
- C+CC
- 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
- Vulnerable module: jpeg-js
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › jimp@0.9.8 › @jimp/types@0.9.8 › @jimp/jpeg@0.9.8 › jpeg-js@0.3.7Remediation: Upgrade to gulp-favicons@3.0.0.
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › jpeg-js@0.2.0
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jpeg-js@0.1.2
Overview
Affected versions of this package are vulnerable to Denial of Service (DoS) where a particular piece of input will cause to enter an infinite loop and never return.
PoC
- Create a npm workspace
npm init
- Install the
jpeg-js
library - Create a JS file with the following code:
const jpeg = require('jpeg-js');
let buf = Buffer.from( 'ffd8ffc1f151d800ff51d800ffdaffde', 'hex' );
jpeg.decode( buf );
- Run the file and observe that the code never stops running
Details
Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.
Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.
One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.
When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.
Two common types of DoS vulnerabilities:
High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.
Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm
ws
package
Remediation
Upgrade jpeg-js
to version 0.4.4 or higher.
References
high severity
- Vulnerable module: mongodb
- Introduced through: mongodb@2.2.36
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › mongodb@2.2.36Remediation: Upgrade to mongodb@3.1.13.
Overview
mongodb is an official MongoDB driver for Node.js.
Affected versions of this package are vulnerable to Denial of Service (DoS). The package fails to properly catch an exception when a collection name is invalid and the DB does not exist, crashing the application.
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:
- CCC
- CC+C
- C+CC
- 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 mongodb
to version 3.1.13 or higher.
References
high severity
- Vulnerable module: nth-check
- Introduced through: cheerio@0.22.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › cheerio@0.22.0 › css-select@1.2.0 › nth-check@1.0.2
Overview
Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS) when parsing crafted invalid CSS nth-checks, due to the sub-pattern \s*(?:([+-]?)\s*(\d+))?
in RE_NTH_ELEMENT
with quantified overlapping adjacency.
PoC
var nthCheck = require("nth-check")
for(var i = 1; i <= 50000; i++) {
var time = Date.now();
var attack_str = '2n' + ' '.repeat(i*10000)+"!";
try {
nthCheck.parse(attack_str)
}
catch(err) {
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:
- CCC
- CC+C
- C+CC
- 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 nth-check
to version 2.0.1 or higher.
References
high severity
- Vulnerable module: url-regex
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › url-regex@3.2.0
Overview
url-regex is a package with regular expression for matching URLs
Affected versions of this package are vulnerable to Regular Expression Denial of Service (ReDoS). An attacker providing a very long string in String.test
can cause a Denial of Service.
PoC by Nick Baugh
For url-regex
package:
require('url-regex')({ strict: false }).test('018137.113.215.4074.138.129.172220.179.206.94180.213.144.175250.45.147.1364868726sgdm6nohQ')
For urlregex
package:
require('urlregex')({ strict: false }).test('018137.113.215.4074.138.129.172220.179.206.94180.213.144.175250.45.147.1364868726sgdm6nohQ')
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:
- CCC
- CC+C
- C+CC
- 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
There is no fixed version for url-regex
.
References
medium severity
- Vulnerable module: request
- Introduced through: request@2.88.2 and gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › request@2.88.2
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › request@2.88.2
Overview
request is a simplified http request client.
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) due to insufficient checks in the lib/redirect.js
file by allowing insecure redirects in the default configuration, via an attacker-controller server that does a cross-protocol redirect (HTTP to HTTPS, or HTTPS to HTTP).
NOTE: request
package has been deprecated, so a fix is not expected. See https://github.com/request/request/issues/3142.
Remediation
A fix was pushed into the master
branch but not yet published.
References
medium severity
- Vulnerable module: sharp
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4Remediation: Upgrade to gulp-favicons@4.0.0.
Overview
sharp is a High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP, GIF, AVIF and TIFF images
Affected versions of this package are vulnerable to Remote Code Execution (RCE). There is a possible vulnerability in logic that is run only at npm install
time when installing the package. If an attacker has the ability to set the value of the PKG_CONFIG_PATH
environment variable in a build environment then they might be able to use this to inject an arbitrary command at npm install
time. This is not part of any runtime code and does not affect Windows users at all.
Remediation
Upgrade sharp
to version 0.30.5 or higher.
References
medium severity
- Vulnerable module: tar
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › sharp@0.23.4 › tar@5.0.11Remediation: Upgrade to gulp-favicons@3.0.0.
Overview
tar is a full-featured Tar for Node.js.
Affected versions of this package are vulnerable to Uncontrolled Resource Consumption ('Resource Exhaustion') due to the lack of folders count validation during the folder creation process. An attacker who generates a large number of sub-folders can consume memory on the system running the software and even crash the client within few seconds of running it using a path with too many sub-folders inside.
Remediation
Upgrade tar
to version 6.2.1 or higher.
References
medium severity
- Vulnerable module: tough-cookie
- Introduced through: request@2.88.2 and gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › request@2.88.2 › tough-cookie@2.5.0
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › request@2.88.2 › tough-cookie@2.5.0
Overview
tough-cookie is a RFC6265 Cookies and CookieJar module for Node.js.
Affected versions of this package are vulnerable to Prototype Pollution due to improper handling of Cookies when using CookieJar in rejectPublicSuffixes=false
mode. Due to an issue with the manner in which the objects are initialized, an attacker can expose or modify a limited amount of property information on those objects. There is no impact to availability.
PoC
// PoC.js
async function main(){
var tough = require("tough-cookie");
var cookiejar = new tough.CookieJar(undefined,{rejectPublicSuffixes:false});
// Exploit cookie
await cookiejar.setCookie(
"Slonser=polluted; Domain=__proto__; Path=/notauth",
"https://__proto__/admin"
);
// normal cookie
var cookie = await cookiejar.setCookie(
"Auth=Lol; Domain=google.com; Path=/notauth",
"https://google.com/"
);
//Exploit cookie
var a = {};
console.log(a["/notauth"]["Slonser"])
}
main();
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 mergeProperty 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
Freeze the prototype— use
Object.freeze (Object.prototype)
.Require schema validation of JSON input.
Avoid using unsafe recursive merge functions.
Consider using objects without prototypes (for example,
Object.create(null)
), breaking the prototype chain and preventing pollution.As a best practice use
Map
instead ofObject
.
For more information on this vulnerability type:
Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018
Remediation
Upgrade tough-cookie
to version 4.1.3 or higher.
References
medium severity
- Vulnerable module: xmldom
- Introduced through: pdf2table@0.0.1
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › pdf2table@0.0.1 › pdf2json@0.7.1 › xmldom@0.6.0
Overview
xmldom is an A pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module.
Affected versions of this package are vulnerable to Improper Input Validation. It does not correctly escape special characters when serializing elements are removed from their ancestor. This may lead to unexpected syntactic changes during XML processing in some downstream applications.
Note: Customers who use "xmldom" package, should use "@xmldom/xmldom" instead, as "xmldom" is no longer maintained.
Remediation
There is no fixed version for xmldom
.
References
medium severity
- Vulnerable module: jpeg-js
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › jimp@0.9.8 › @jimp/types@0.9.8 › @jimp/jpeg@0.9.8 › jpeg-js@0.3.7Remediation: Upgrade to gulp-favicons@3.0.0.
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › jpeg-js@0.2.0
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jpeg-js@0.1.2
Overview
Affected versions of this package are vulnerable to Denial of Service (DoS). The attacker could manipulate the exif data in the image file such as change the image pixel to 64250x64250pixels. If the module loaded the crafted image, it tries to allocate 4128062500 pixels into memory.
Details
Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.
Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.
One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.
When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.
Two common types of DoS vulnerabilities:
High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.
Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm
ws
package
Remediation
Upgrade jpeg-js
to version 0.4.0 or higher.
References
medium severity
- Vulnerable module: minimist
- Introduced through: gulp-favicons@2.4.0 and pdf2table@0.0.1
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › mkdirp@0.5.1 › minimist@0.0.8
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › pdf2table@0.0.1 › pdf2json@0.7.1 › optimist@0.6.1 › minimist@0.0.10
Overview
minimist is a parse argument options module.
Affected versions of this package are vulnerable to Prototype Pollution. The library could be tricked into adding or modifying properties of Object.prototype
using a constructor
or __proto__
payload.
PoC by Snyk
require('minimist')('--__proto__.injected0 value0'.split(' '));
console.log(({}).injected0 === 'value0'); // true
require('minimist')('--constructor.prototype.injected1 value1'.split(' '));
console.log(({}).injected1 === 'value1'); // true
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 mergeProperty 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
Freeze the prototype— use
Object.freeze (Object.prototype)
.Require schema validation of JSON input.
Avoid using unsafe recursive merge functions.
Consider using objects without prototypes (for example,
Object.create(null)
), breaking the prototype chain and preventing pollution.As a best practice use
Map
instead ofObject
.
For more information on this vulnerability type:
Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018
Remediation
Upgrade minimist
to version 0.2.1, 1.2.3 or higher.
References
medium severity
- Vulnerable module: xml2js
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › xml2js@0.4.23Remediation: Upgrade to gulp-favicons@4.0.0.
Overview
Affected versions of this package are vulnerable to Prototype Pollution due to allowing an external attacker to edit or add new properties to an object. This is possible because the application does not properly validate incoming JSON keys, thus allowing the __proto__
property to be edited.
PoC
var parseString = require('xml2js').parseString;
let normal_user_request = "<role>admin</role>";
let malicious_user_request = "<__proto__><role>admin</role></__proto__>";
const update_user = (userProp) => {
// A user cannot alter his role. This way we prevent privilege escalations.
parseString(userProp, function (err, user) {
if(user.hasOwnProperty("role") && user?.role.toLowerCase() === "admin") {
console.log("Unauthorized Action");
} else {
console.log(user?.role[0]);
}
});
}
update_user(normal_user_request);
update_user(malicious_user_request);
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 mergeProperty 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
Freeze the prototype— use
Object.freeze (Object.prototype)
.Require schema validation of JSON input.
Avoid using unsafe recursive merge functions.
Consider using objects without prototypes (for example,
Object.create(null)
), breaking the prototype chain and preventing pollution.As a best practice use
Map
instead ofObject
.
For more information on this vulnerability type:
Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018
Remediation
Upgrade xml2js
to version 0.5.0 or higher.
References
medium severity
new
- Vulnerable module: phin
- Introduced through: gulp-favicons@2.4.0
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › jimp@0.9.8 › @jimp/custom@0.9.8 › @jimp/core@0.9.8 › phin@2.9.3
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › jimp@0.9.8 › @jimp/custom@0.9.8 › @jimp/core@0.9.8 › load-bmfont@1.4.1 › phin@2.9.3
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › jimp@0.9.8 › @jimp/plugins@0.9.8 › @jimp/plugin-print@0.9.8 › load-bmfont@1.4.1 › phin@2.9.3
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › load-bmfont@1.4.1 › phin@2.9.3
Overview
phin is a The ultra-lightweight Node.js HTTP client
Affected versions of this package are vulnerable to Information Exposure Through Sent Data due to the handling of HTTP headers during redirects when followRedirects
is enabled. An attacker can potentially intercept sensitive information by exploiting how headers are included in outgoing requests after a redirect.
Remediation
Upgrade phin
to version 3.7.1 or higher.
References
low severity
- Vulnerable module: @angular/core
- Introduced through: @angular/core@4.4.7
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › @angular/core@4.4.7Remediation: Upgrade to @angular/core@11.0.5.
Overview
@angular/core is a package that lets you write client-side web applications as if you had a smarter browser. It also lets you use HTML as your template language and lets you extend HTML’s syntax to express your application’s components clearly and succinctly.
Affected versions of this package are vulnerable to Cross-site Scripting (XSS) in development, with SSR enabled.
Details
A cross-site scripting attack occurs when the attacker tricks a legitimate web-based application or site to accept a request as originating from a trusted source.
This is done by escaping the context of the web application; the web application then delivers that data to its users along with other trusted dynamic content, without validating it. The browser unknowingly executes malicious script on the client side (through client-side languages; usually JavaScript or HTML) in order to perform actions that are otherwise typically blocked by the browser’s Same Origin Policy.
Injecting malicious code is the most prevalent manner by which XSS is exploited; for this reason, escaping characters in order to prevent this manipulation is the top method for securing code against this vulnerability.
Escaping means that the application is coded to mark key characters, and particularly key characters included in user input, to prevent those characters from being interpreted in a dangerous context. For example, in HTML, <
can be coded as <
; and >
can be coded as >
; in order to be interpreted and displayed as themselves in text, while within the code itself, they are used for HTML tags. If malicious content is injected into an application that escapes special characters and that malicious content uses <
and >
as HTML tags, those characters are nonetheless not interpreted as HTML tags by the browser if they’ve been correctly escaped in the application code and in this way the attempted attack is diverted.
The most prominent use of XSS is to steal cookies (source: OWASP HttpOnly) and hijack user sessions, but XSS exploits have been used to expose sensitive information, enable access to privileged services and functionality and deliver malware.
Types of attacks
There are a few methods by which XSS can be manipulated:
Type | Origin | Description |
---|---|---|
Stored | Server | The malicious code is inserted in the application (usually as a link) by the attacker. The code is activated every time a user clicks the link. |
Reflected | Server | The attacker delivers a malicious link externally from the vulnerable web site application to a user. When clicked, malicious code is sent to the vulnerable web site, which reflects the attack back to the user’s browser. |
DOM-based | Client | The attacker forces the user’s browser to render a malicious page. The data in the page itself delivers the cross-site scripting data. |
Mutated | The attacker injects code that appears safe, but is then rewritten and modified by the browser, while parsing the markup. An example is rebalancing unclosed quotation marks or even adding quotation marks to unquoted parameters. |
Affected environments
The following environments are susceptible to an XSS attack:
- Web servers
- Application servers
- Web application environments
How to prevent
This section describes the top best practices designed to specifically protect your code:
- Sanitize data input in an HTTP request before reflecting it back, ensuring all data is validated, filtered or escaped before echoing anything back to the user, such as the values of query parameters during searches.
- Convert special characters such as
?
,&
,/
,<
,>
and spaces to their respective HTML or URL encoded equivalents. - Give users the option to disable client-side scripts.
- Redirect invalid requests.
- Detect simultaneous logins, including those from two separate IP addresses, and invalidate those sessions.
- Use and enforce a Content Security Policy (source: Wikipedia) to disable any features that might be manipulated for an XSS attack.
- Read the documentation for any of the libraries referenced in your code to understand which elements allow for embedded HTML.
Remediation
Upgrade @angular/core
to version 11.0.5, 11.1.0-next.3 or higher.
References
low severity
- Vulnerable module: minimist
- Introduced through: gulp-favicons@2.4.0 and pdf2table@0.0.1
Detailed paths
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › gulp-favicons@2.4.0 › favicons@5.5.0 › to-ico@1.1.5 › resize-img@1.1.2 › jimp@0.2.28 › mkdirp@0.5.1 › minimist@0.0.8
-
Introduced through: novaXfer@mattbdean/novaxfer#80eeeecd26c4942f66fe2b862136df02120d587c › pdf2table@0.0.1 › pdf2json@0.7.1 › optimist@0.6.1 › minimist@0.0.10
Overview
minimist is a parse argument options module.
Affected versions of this package are vulnerable to Prototype Pollution due to a missing handler to Function.prototype
.
Notes:
This vulnerability is a bypass to CVE-2020-7598
The reason for the different CVSS between CVE-2021-44906 to CVE-2020-7598, is that CVE-2020-7598 can pollute objects, while CVE-2021-44906 can pollute only function.
PoC by Snyk
require('minimist')('--_.constructor.constructor.prototype.foo bar'.split(' '));
console.log((function(){}).foo); // bar
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 mergeProperty 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
Freeze the prototype— use
Object.freeze (Object.prototype)
.Require schema validation of JSON input.
Avoid using unsafe recursive merge functions.
Consider using objects without prototypes (for example,
Object.create(null)
), breaking the prototype chain and preventing pollution.As a best practice use
Map
instead ofObject
.
For more information on this vulnerability type:
Arteau, Oliver. “JavaScript prototype pollution attack in NodeJS application.” GitHub, 26 May 2018
Remediation
Upgrade minimist
to version 0.2.4, 1.2.6 or higher.