CVE-2020-8268
📋 TL;DR
This is a prototype pollution vulnerability in the json8-merge-patch npm package that allows attackers to modify JavaScript object prototypes. Applications using vulnerable versions of this package are affected, potentially leading to remote code execution or privilege escalation.
💻 Affected Systems
- json8-merge-patch npm package
📦 What is this software?
Json8 Merge Patch by Json8 Merge Patch Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Privilege escalation, unauthorized data access, or denial of service through application manipulation.
If Mitigated
Limited impact if proper input validation and sandboxing are implemented, potentially only causing application crashes.
🎯 Exploit Status
Exploitation requires crafting malicious JSON input that triggers prototype pollution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.3
Vendor Advisory: https://github.com/sonnyp/JSON8/security/advisories/GHSA-9c6c-wf6q-7c4h
Restart Required: Yes
Instructions:
1. Update package.json to specify json8-merge-patch version 1.0.3 or higher. 2. Run 'npm update json8-merge-patch'. 3. Restart all Node.js applications using this package.
🔧 Temporary Workarounds
Input Validation
allImplement strict input validation to reject malformed JSON objects before processing.
Package Lock
allUse npm audit fix to automatically update vulnerable dependencies.
npm audit fix
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to block malicious JSON payloads.
- Isolate affected applications in network segments with restricted access.
🔍 How to Verify
Check if Vulnerable:
Check package.json for json8-merge-patch version < 1.0.3 or run 'npm list json8-merge-patch'.Check Version:
npm list json8-merge-patch | grep json8-merge-patchVerify Fix Applied:
Confirm json8-merge-patch version is 1.0.3 or higher using 'npm list json8-merge-patch'.📡 Detection & Monitoring
Log Indicators:
- Unusual JSON parsing errors
- Application crashes during JSON processing
- Suspicious prototype modification attempts
Network Indicators:
- Malformed JSON payloads in HTTP requests
- Unexpected object property modifications
SIEM Query:
source="application_logs" AND ("json8-merge-patch" OR "prototype pollution")