CVE-2020-28490
📋 TL;DR
CVE-2020-28490 is a command injection vulnerability in async-git npm package versions before 1.13.2. Attackers can execute arbitrary shell commands by injecting shell metacharacters (like backticks) into git command arguments. This affects any application using vulnerable async-git versions to execute git operations.
💻 Affected Systems
- async-git npm package
📦 What is this software?
Async Git by Async Git Project
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise allowing remote code execution, data theft, lateral movement, and complete control of affected systems.
Likely Case
Arbitrary command execution with application user privileges, potentially leading to data exfiltration, service disruption, or further exploitation.
If Mitigated
Limited impact due to input validation, sandboxing, or restricted user permissions preventing privilege escalation.
🎯 Exploit Status
Simple command injection via backticks demonstrated in vulnerability reports. Exploitation requires user input to reach vulnerable functions.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.13.2 and later
Vendor Advisory: https://github.com/omrilotan/async-git/commit/d1950a5021f4e19d92f347614be0d85ce991510d
Restart Required: No
Instructions:
1. Update async-git package to version 1.13.2 or later using npm: npm update async-git@latest 2. Verify the update with: npm list async-git 3. Test application functionality after update.
🔧 Temporary Workarounds
Input validation and sanitization
allImplement strict input validation to reject shell metacharacters before passing to async-git functions.
// JavaScript example: validate input before async-git call
function sanitizeInput(input) {
const dangerousChars = /[`$();|&<>]/;
if (dangerousChars.test(input)) {
throw new Error('Invalid input');
}
return input;
}
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user inputs passed to async-git functions.
- Run application with minimal privileges and in isolated environments (containers, sandboxes) to limit impact.
🔍 How to Verify
Check if Vulnerable:
Check package.json or run: npm list async-git | grep async-gitCheck Version:
npm list async-git | grep async-gitVerify Fix Applied:
Verify installed version is 1.13.2 or higher: npm list async-git📡 Detection & Monitoring
Log Indicators:
- Unusual git command executions with shell metacharacters
- Suspicious child process spawns from node.js application
- Error logs showing command injection attempts
Network Indicators:
- Unexpected outbound connections from application server
- Data exfiltration patterns
SIEM Query:
process.name:node AND cmdline:*backtick* OR cmdline:*`*🔗 References
- https://github.com/omrilotan/async-git/commit/d1950a5021f4e19d92f347614be0d85ce991510d
- https://github.com/omrilotan/async-git/pull/14
- https://snyk.io/vuln/SNYK-JS-ASYNCGIT-1064877
- https://github.com/omrilotan/async-git/commit/d1950a5021f4e19d92f347614be0d85ce991510d
- https://github.com/omrilotan/async-git/pull/14
- https://snyk.io/vuln/SNYK-JS-ASYNCGIT-1064877
