CVE-2024-27980: Node.js child_process RCE Vulnerability

CVE-2024-27980 Overview

CVE-2024-27980 is a command injection vulnerability affecting Node.js due to improper handling of batch files in child_process.spawn and child_process.spawnSync functions. A malicious command line argument can inject arbitrary commands and achieve code execution even when the shell option is not enabled, bypassing expected security restrictions.

Critical Impact

Attackers can achieve arbitrary code execution on systems running vulnerable Node.js applications by exploiting improper batch file handling in child process spawning functions.

Affected Products

• Node.js applications using child_process.spawn() with batch files
• Node.js applications using child_process.spawnSync() with batch files
• Systems running affected Node.js versions on Windows platforms

Discovery Timeline

• 2025-01-09 - CVE CVE-2024-27980 published to NVD
• 2025-01-09 - Last updated in NVD database

Technical Details for CVE-2024-27980

Vulnerability Analysis

This vulnerability is classified as CWE-77 (Command Injection) and allows attackers to execute arbitrary commands on the target system. The issue stems from how Node.js handles batch file execution through its child process APIs. When child_process.spawn() or child_process.spawnSync() are called to execute batch files (.bat or .cmd), the implementation fails to properly sanitize command line arguments, allowing specially crafted input to break out of the intended command context.

What makes this vulnerability particularly dangerous is that it bypasses the expected security behavior where setting shell: false (the default) should prevent command injection attacks. Developers who believed their applications were protected by not enabling shell execution may find their applications are actually vulnerable when processing batch files on Windows systems.

Root Cause

The root cause lies in the improper handling of batch file arguments within Node.js's child process module. On Windows, batch files are processed by cmd.exe, which has its own parsing rules for special characters. When Node.js spawns a batch file without the shell option, it still ultimately relies on the Windows command interpreter to execute the batch file, but the argument sanitization does not account for all cmd.exe metacharacters that could be used to inject additional commands.

The vulnerability occurs because arguments passed to batch files are not properly escaped for the Windows command interpreter context, allowing command separators and other special characters to be interpreted as command delimiters rather than literal argument content.

Attack Vector

The attack requires network access and exploits the child process spawning mechanism. An attacker can craft malicious input that, when passed as an argument to a batch file being executed via child_process.spawn() or child_process.spawnSync(), will break out of the intended argument context and execute arbitrary commands.

The attack scenario typically involves:

1. An application accepting user-controlled input that is eventually passed as an argument to a batch file execution
2. The application using child_process.spawn() or child_process.spawnSync() to execute a batch file with the user-controlled argument
3. The attacker crafting input containing Windows command injection characters that are not properly sanitized
4. The injected commands executing with the privileges of the Node.js process

For detailed technical analysis, refer to the OpenWall OSS-Security advisories documenting this vulnerability.

Detection Methods for CVE-2024-27980

Indicators of Compromise

• Unexpected process spawning from Node.js applications, particularly cmd.exe with suspicious arguments
• Unusual command execution patterns in application logs where batch files are invoked
• Network connections or file system modifications originating from Node.js worker processes
• Presence of command injection characters in logged input parameters passed to child processes

Detection Strategies

• Monitor for child_process.spawn and child_process.spawnSync calls executing .bat or .cmd files with user-controlled arguments
• Implement input validation logging to detect command injection attempt patterns such as &, |, >, <, and ^ characters in arguments
• Deploy application security monitoring to detect anomalous command execution from Node.js processes
• Use runtime application self-protection (RASP) solutions to monitor child process creation

Monitoring Recommendations

• Enable detailed logging for all child process executions in Node.js applications
• Implement alerting for unusual process chains where Node.js spawns unexpected child processes
• Monitor system calls related to process creation from Node.js application contexts
• Review application logs for patterns indicating attempted command injection

How to Mitigate CVE-2024-27980

Immediate Actions Required

• Audit all Node.js applications for usage of child_process.spawn() or child_process.spawnSync() with batch files
• Implement strict input validation and sanitization for any user-controlled data passed to child process functions
• Consider replacing batch file execution with native Node.js alternatives where possible
• Apply vendor patches when available from the Node.js project

Patch Information

Security updates have been announced through distribution channels including Fedora. Administrators should apply the latest Node.js security updates from their respective package managers. For Fedora users, updates are available through the Fedora Package Announcements. Additional security advisories and patch information can be found in the OpenWall OSS-Security mailing list.

Workarounds

• Avoid using child_process.spawn() or child_process.spawnSync() to execute batch files with user-controlled arguments
• Implement a strict allowlist for acceptable argument values when batch file execution is required
• Use alternative approaches such as invoking commands directly without batch file wrappers
• Apply defense-in-depth by running Node.js applications with minimal privileges to limit the impact of successful exploitation

# Configuration example
# Restrict Node.js process capabilities on Linux systems
# Example systemd service hardening for Node.js applications
# /etc/systemd/system/nodeapp.service.d/security.conf
[Service]
NoNewPrivileges=true
PrivateTmp=true
ProtectSystem=strict
ProtectHome=true
CapabilityBoundingSet=
RestrictNamespaces=true