CVE-2020-22876
📋 TL;DR
A buffer overflow vulnerability in QuickJS's quickjs.c allows remote attackers to cause denial of service by crashing the application. This affects systems running QuickJS before the 2020-07-05 release, potentially impacting applications using this JavaScript engine.
💻 Affected Systems
- QuickJS JavaScript Engine
📦 What is this software?
Quickjs by Quickjs Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise if combined with other vulnerabilities, though this specific CVE is documented as DoS.
Likely Case
Denial of service through application crash when processing malicious JavaScript input.
If Mitigated
Minimal impact if proper input validation and memory protections are in place.
🎯 Exploit Status
The GitHub issue contains proof-of-concept details showing buffer overflow triggering.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2020-07-05 release
Vendor Advisory: https://github.com/ldarren/QuickJS/issues/11
Restart Required: Yes
Instructions:
1. Update QuickJS to version 2020-07-05 or later. 2. Recompile any applications using QuickJS. 3. Restart affected services.
🔧 Temporary Workarounds
Input Validation
allImplement strict input validation for JavaScript code processed by QuickJS
Memory Protection
linuxEnable ASLR and other memory protection mechanisms on the host system
sysctl -w kernel.randomize_va_space=2
🧯 If You Can't Patch
- Isolate QuickJS instances in containers or sandboxes
- Implement network segmentation to limit exposure
🔍 How to Verify
Check if Vulnerable:
Check QuickJS version: quickjs --version or examine source code dateCheck Version:
quickjs --versionVerify Fix Applied:
Verify version is 2020-07-05 or later and test with known PoC inputs📡 Detection & Monitoring
Log Indicators:
- Application crashes
- Segmentation faults in QuickJS processes
- Memory access violation errors
Network Indicators:
- Unusual JavaScript payloads to QuickJS endpoints
SIEM Query:
process_name:"quickjs" AND (event_type:"crash" OR error:"segmentation fault")