CVE-2020-8147
📋 TL;DR
CVE-2020-8147 is a prototype pollution vulnerability in the utils-extend npm package that allows attackers to modify JavaScript object prototypes. This can lead to remote code execution or denial of service in applications using this package. Anyone using utils-extend version 1.0.8 or earlier is affected.
💻 Affected Systems
- utils-extend npm package
📦 What is this software?
Utils Extend by Utils Extend Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Denial of service through application crashes or prototype pollution leading to unpredictable behavior.
If Mitigated
Limited impact if proper input validation and sandboxing are implemented at application level.
🎯 Exploit Status
Exploitation requires attacker to control input to vulnerable functions. Public proof-of-concept demonstrates prototype pollution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.9
Vendor Advisory: https://www.npmjs.com/advisories/1500
Restart Required: Yes
Instructions:
1. Update package.json to use utils-extend version 1.0.9 or later. 2. Run 'npm update utils-extend'. 3. Restart all affected applications.
🔧 Temporary Workarounds
Input validation wrapper
allImplement strict input validation for all user-controlled data passed to utils-extend functions
Package replacement
allReplace utils-extend with alternative packages like lodash.merge or object-assign
npm uninstall utils-extend
npm install lodash.merge
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user-controlled data
- Deploy web application firewall with prototype pollution detection rules
🔍 How to Verify
Check if Vulnerable:
Check package.json or run 'npm list utils-extend' to see installed versionCheck Version:
npm list utils-extend | grep utils-extendVerify Fix Applied:
Verify version is 1.0.9 or later with 'npm list utils-extend'📡 Detection & Monitoring
Log Indicators:
- Unusual application crashes
- Unexpected prototype modifications in logs
- Suspicious input patterns
Network Indicators:
- Malformed JSON payloads
- Requests with specially crafted object properties
SIEM Query:
source="application.log" AND ("prototype" OR "__proto__") AND "utils-extend"