CVE-2018-3786
📋 TL;DR
CVE-2018-3786 is a command injection vulnerability in egg-scripts versions before 2.8.1 that allows attackers to execute arbitrary shell commands through malicious command line arguments. This affects any system using vulnerable egg-scripts versions, particularly Node.js applications built with the Egg.js framework.
💻 Affected Systems
- egg-scripts
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise allowing attacker to execute arbitrary commands with the privileges of the egg-scripts process, potentially leading to data theft, system takeover, or lateral movement.
Likely Case
Remote code execution leading to application compromise, data exfiltration, or deployment of malware/backdoors.
If Mitigated
Limited impact if proper input validation and sandboxing are implemented, though command injection would still be possible.
🎯 Exploit Status
Exploitation is straightforward - attackers can inject shell commands through command line arguments. Public proof-of-concept exists in HackerOne report.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.8.1
Vendor Advisory: https://github.com/eggjs/egg-scripts/blob/2.8.1/History.md
Restart Required: Yes
Instructions:
1. Update egg-scripts to version 2.8.1 or later using npm: npm update egg-scripts@latest 2. Restart any services using egg-scripts 3. Verify the update with: npm list egg-scripts
🔧 Temporary Workarounds
Input Validation Wrapper
allCreate a wrapper script that validates and sanitizes command line arguments before passing to egg-scripts
#!/bin/bash
# Validate arguments before passing to egg-scripts
# Implement strict validation for expected arguments
# Reject any arguments with shell metacharacters
🧯 If You Can't Patch
- Implement strict input validation for all command line arguments passed to egg-scripts
- Run egg-scripts with minimal privileges and in a sandboxed/containerized environment
🔍 How to Verify
Check if Vulnerable:
Check egg-scripts version: npm list egg-scripts | grep egg-scriptsCheck Version:
npm list egg-scripts | grep egg-scriptsVerify Fix Applied:
Verify version is 2.8.1 or higher: npm list egg-scripts | grep egg-scripts📡 Detection & Monitoring
Log Indicators:
- Unusual command execution patterns in system logs
- Suspicious arguments passed to egg-scripts processes
- Unexpected child process spawns from egg-scripts
Network Indicators:
- Unexpected outbound connections from egg-scripts processes
- Command and control traffic from affected systems
SIEM Query:
Process execution where parent_process contains 'egg-scripts' AND command_line contains shell metacharacters like ;, &, |, $, (, ), {, }