CVE-2020-28278
📋 TL;DR
This CVE describes a prototype pollution vulnerability in the 'shvl' JavaScript library versions 1.0.0 through 2.0.1. Attackers can manipulate object prototypes to cause denial of service or potentially achieve remote code execution. Any application using vulnerable versions of this library is affected.
💻 Affected Systems
- shvl JavaScript library
📦 What is this software?
Shvl by Shvl Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or lateral movement within the network.
Likely Case
Denial of service through application crashes or instability, potentially leading to data corruption.
If Mitigated
Limited impact if proper input validation and sandboxing are implemented, though prototype pollution remains dangerous.
🎯 Exploit Status
Prototype pollution vulnerabilities are well-understood and often easily exploitable with publicly available techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.2 and later
Vendor Advisory: https://github.com/robinvdvleuten/shvl/security/advisories
Restart Required: Yes
Instructions:
1. Update package.json to use shvl version 2.0.2 or later. 2. Run 'npm update shvl' or 'yarn upgrade shvl'. 3. Restart all services using the library. 4. Test application functionality.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement strict input validation to prevent malicious object manipulation.
Object.freeze() on Prototypes
allUse Object.freeze() on critical object prototypes to prevent pollution.
Object.freeze(Object.prototype);
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user-controlled data passed to shvl functions.
- Isolate the vulnerable component in a sandboxed environment with limited permissions.
🔍 How to Verify
Check if Vulnerable:
Check package.json or package-lock.json for shvl version. If version is between 1.0.0 and 2.0.1 inclusive, the system is vulnerable.Check Version:
npm list shvl | grep shvl || yarn list --pattern shvlVerify Fix Applied:
Verify shvl version is 2.0.2 or later in package.json and that the application functions correctly after update.📡 Detection & Monitoring
Log Indicators:
- Unexpected application crashes
- Unusual object property modifications in logs
- Error messages related to prototype pollution
Network Indicators:
- Unusual HTTP requests with crafted JSON/object payloads
- Requests targeting endpoints using shvl library
SIEM Query:
source="application.logs" AND ("prototype pollution" OR "shvl" OR "unexpected property")🔗 References
- https://github.com/robinvdvleuten/shvl/blob/bef0a3ebade444cc6b297147ecf5242308f0892e/index.js#L10
- https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28278
- https://github.com/robinvdvleuten/shvl/blob/bef0a3ebade444cc6b297147ecf5242308f0892e/index.js#L10
- https://www.whitesourcesoftware.com/vulnerability-database/CVE-2020-28278
