Find, fix and prevent vulnerabilities in your code.

Overview

com.fasterxml.jackson.core:jackson-databind is a library which contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor.

Affected versions of this package are vulnerable to Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') through NioPathDeserializer in src/main/java/com/fasterxml/jackson/databind/ext/NioPathDeserializer.java. An attacker can force readValue() to resolve an attacker-controlled java.nio.file.Path URI by supplying a non-file scheme such as jar:, http:, s3:, or a custom provider scheme in untrusted JSON. That input reaches new URI(value) and then Path.of(uri), which falls back to ServiceLoader<FileSystemProvider> resolution and can invoke a matching provider’s getPath(uri) during deserialization. The result is unintended provider loading and provider-driven path handling inside the application, which can trigger denial of service or other side effects depending on what FileSystemProvider implementations are present on the classpath.

Remediation

Upgrade com.fasterxml.jackson.core:jackson-databind to version 2.18.10, 2.21.6, 2.22.2 or higher.

References

• GitHub Commit
• GitHub Commit
• GitHub Commit
• GitHub PR
• Maintainer's Advisory

Overview

com.fasterxml.jackson.core:jackson-databind is a library which contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor.

Affected versions of this package are vulnerable to Deserialization of Untrusted Data in the isSafeSubType() method of DefaultBaseTypeLimitingValidator, whose denylist of unsafe base types omits java.lang.Comparable, so the method returns true for any subtype resolved under a Comparable base. An attacker can trigger instantiation of arbitrary classes that implement Comparable, such as java.io.File to reach path-traversal primitives, by sending JSON with attacker-controlled type identifiers. This requires the application to use a bare @JsonTypeInfo with the default validator and no explicit PolymorphicTypeValidator, and a property or class whose declared base type is Comparable.

Workaround

This vulnerability can be avoided by configuring an explicit restrictive PolymorphicTypeValidator, such as a BasicPolymorphicTypeValidator allowlist passed to activateDefaultTyping(), instead of relying on the default validator.

Note: The discoverer of this vulnerability reports that "I have not identified a class implementing Comparable that yields code execution purely through deserialization".

Details

Serialization is a process of converting an object into a sequence of bytes which can be persisted to a disk or database or can be sent through streams. The reverse process of creating object from sequence of bytes is called deserialization. Serialization is commonly used for communication (sharing objects between multiple hosts) and persistence (store the object state in a file or a database). It is an integral part of popular protocols like Remote Method Invocation (RMI), Java Management Extension (JMX), Java Messaging System (JMS), Action Message Format (AMF), Java Server Faces (JSF) ViewState, etc.

Deserialization of untrusted data (CWE-502) is when the application deserializes untrusted data without sufficiently verifying that the resulting data will be valid, thus allowing the attacker to control the state or the flow of the execution.

Remediation

Upgrade com.fasterxml.jackson.core:jackson-databind to version 2.18.10, 2.21.6, 2.22.2 or higher.

References

• GitHub Advisory
• GitHub Commit
• GitHub Issue
• GitHub PR

LGPL-2.1 license

LGPL-2.1 license

EPL-1.0 license