CVE-2020-28271
📋 TL;DR
This is a prototype pollution vulnerability in the 'deephas' npm package that allows attackers to modify object prototypes, potentially leading to denial of service or remote code execution. Any application using vulnerable versions of deephas is affected, particularly Node.js applications that process untrusted user input.
💻 Affected Systems
- deephas npm package
📦 What is this software?
Deephas by Deephas 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 instability, with potential for limited code execution in specific configurations.
If Mitigated
Limited impact if input validation and sandboxing prevent prototype pollution, though application instability may still occur.
🎯 Exploit Status
Prototype pollution vulnerabilities are well-understood and often have public proof-of-concept exploits available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.6 and later
Vendor Advisory: https://github.com/sharpred/deepHas/commit/2fe011713a6178c50f7deb6f039a8e5435981e20
Restart Required: Yes
Instructions:
1. Update package.json to specify 'deephas': '^1.0.6'. 2. Run 'npm update deephas'. 3. Restart your application. 4. Test functionality.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement strict input validation to prevent prototype pollution payloads from reaching vulnerable functions.
Object.freeze on Prototypes
allFreeze Object.prototype and other critical prototypes to prevent pollution.
Object.freeze(Object.prototype);
Object.freeze(Object.prototype.__proto__);
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user-controlled data
- Use application firewalls or reverse proxies to filter malicious payloads
- Isolate vulnerable applications in restricted network segments
- Monitor for abnormal application behavior and crashes
🔍 How to Verify
Check if Vulnerable:
Check package.json or run 'npm list deephas' to see installed version. If version is between 1.0.0 and 1.0.5 inclusive, you are vulnerable.Check Version:
npm list deephas | grep deephasVerify Fix Applied:
After updating, run 'npm list deephas' to confirm version 1.0.6 or higher is installed. Test application functionality with known safe inputs.📡 Detection & Monitoring
Log Indicators:
- Application crashes or unexpected terminations
- Unusual error messages related to object properties or prototypes
- High CPU/memory usage spikes
Network Indicators:
- Unusual outbound connections from application
- Requests containing prototype pollution patterns (__proto__, constructor, prototype)
SIEM Query:
source="application.logs" AND ("__proto__" OR "constructor" OR "prototype") AND status="error"🔗 References
- https://github.com/sharpred/deepHas/commit/2fe011713a6178c50f7deb6f039a8e5435981e20
- https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28271
- https://github.com/sharpred/deepHas/commit/2fe011713a6178c50f7deb6f039a8e5435981e20
- https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28271
