CVE-2022-29599: Apache Maven Shared Utils RCE Vulnerability

CVE-2022-29599 Overview

CVE-2022-29599 is a command injection vulnerability in Apache Maven maven-shared-utils prior to version 3.3.3. The Commandline class can emit double-quoted strings without proper escaping, allowing attackers to execute arbitrary shell commands through specially crafted input. This vulnerability affects build processes and CI/CD pipelines that rely on Maven for dependency management and build automation.

Critical Impact

Attackers can achieve remote code execution by injecting malicious shell commands through improperly escaped strings in Maven build processes, potentially compromising build servers and software supply chains.

Affected Products

• Apache Maven Shared Utils (versions prior to 3.3.3)
• Debian Linux 10.0
• Debian Linux 11.0

Discovery Timeline

• 2022-05-23 - CVE-2022-29599 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2022-29599

Vulnerability Analysis

This vulnerability stems from improper output encoding (CWE-116) in the Apache Maven maven-shared-utils library. The Commandline class is responsible for constructing command-line strings that are passed to the operating system's shell for execution. When building these command strings, the class wraps arguments in double quotes but fails to properly escape special characters within those quoted strings.

The fundamental issue is that shell interpreters treat certain characters as metacharacters even within double quotes. Characters such as backticks, dollar signs, and backslashes can trigger command substitution or variable expansion. When user-controlled input containing these characters is passed through the Commandline class without proper sanitization, an attacker can break out of the intended context and inject arbitrary commands.

This type of shell injection vulnerability is particularly dangerous in build automation contexts because build processes often run with elevated privileges and have access to source code, credentials, and deployment infrastructure.

Root Cause

The root cause is insufficient input escaping in the Commandline class when constructing shell commands with double-quoted strings. The class does not properly sanitize special shell metacharacters before incorporating them into the command string. According to Apache JIRA Issue MSHARED-297, the fix involves properly escaping characters that have special meaning within double-quoted shell strings.

Attack Vector

The attack is network-based and can be executed without authentication or user interaction. An attacker who can influence the arguments passed to Maven build commands—such as through malicious project configuration files, dependency names, or build parameters—can inject shell metacharacters that escape the double-quoted context. When the command is executed, the injected payload runs with the privileges of the Maven process.

Common attack scenarios include:

• Malicious pom.xml files in open-source dependencies
• Crafted build parameters in CI/CD pipeline configurations
• Exploitation through plugin parameters that accept user-controlled values

The vulnerability mechanism involves the Commandline class failing to escape shell metacharacters within double-quoted arguments. When constructing command strings, characters like backticks and $() syntax can trigger command substitution in shells. For detailed technical information, see the GitHub Pull Request that addresses this issue.

Detection Methods for CVE-2022-29599

Indicators of Compromise

• Unexpected process spawning from Maven build processes or Java applications
• Unusual network connections originating from build servers during Maven execution
• Modified or suspicious pom.xml files containing unusual characters in plugin configurations
• Anomalous shell activity correlating with Maven build timestamps

Detection Strategies

• Monitor for child processes spawned by Maven that execute shell commands with unusual arguments
• Implement file integrity monitoring on Maven configuration files and build scripts
• Review CI/CD pipeline logs for unexpected command executions during build phases
• Scan dependencies and project files for suspicious strings containing shell metacharacters

Monitoring Recommendations

• Enable comprehensive logging for Maven builds and analyze for anomalous patterns
• Deploy runtime application security monitoring on build servers
• Implement network traffic analysis for build infrastructure to detect unauthorized connections
• Configure alerts for any modification to Maven-related configuration files

How to Mitigate CVE-2022-29599

Immediate Actions Required

• Upgrade Apache Maven Shared Utils to version 3.3.3 or later immediately
• Audit all Maven projects to identify usage of vulnerable maven-shared-utils versions
• Review CI/CD pipeline configurations for potentially malicious input sources
• Implement input validation on any user-controllable build parameters

Patch Information

Apache has released version 3.3.3 of maven-shared-utils that properly escapes shell metacharacters in the Commandline class. The fix is documented in the GitHub Pull Request. Debian has also released security updates addressing this vulnerability as documented in DSA-5242 and the Debian LTS Security Announcement.

Workarounds

• Isolate build environments using containers or virtual machines to limit blast radius
• Restrict network access from build servers to minimize data exfiltration risk
• Implement strict code review processes for all changes to build configuration files
• Use dependency scanning tools to identify and flag vulnerable library versions

# Update maven-shared-utils in pom.xml
# Ensure dependency version is 3.3.3 or higher
mvn versions:display-dependency-updates | grep maven-shared-utils

# For Debian systems, apply security updates
sudo apt-get update && sudo apt-get upgrade maven-shared-utils