CVE-2024-45402
📋 TL;DR
Picotls TLS library contains a double-free vulnerability when parsing malicious TLS handshake messages, which could lead to process crashes or potentially arbitrary code execution. This affects applications using picotls with vulnerable crypto backends. Systems using picotls for TLS communication are at risk.
💻 Affected Systems
- picotls TLS library
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Arbitrary code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Process crashes causing denial of service and potential service disruption.
If Mitigated
Process termination via malloc abort with minimal impact if proper isolation exists.
🎯 Exploit Status
Exploitation requires sending crafted TLS handshake messages; complexity depends on malloc implementation and crypto backend.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit 9b88159ce763d680e4a13b6e8f3171ae923a535d
Vendor Advisory: https://github.com/h2o/picotls/security/advisories/GHSA-w7c8-wjx9-vvvv
Restart Required: Yes
Instructions:
1. Update picotls to include commit 9b88159ce763d680e4a13b6e8f3171ae923a535d. 2. Rebuild applications using picotls. 3. Restart affected services.
🔧 Temporary Workarounds
Network filtering
allBlock or filter malicious TLS handshake messages at network perimeter.
Memory hardening
linuxUse malloc implementations with enhanced security features (like glibc with FORTIFY_SOURCE).
export CFLAGS="-D_FORTIFY_SOURCE=2"
🧯 If You Can't Patch
- Isolate affected systems in segmented network zones
- Implement strict network monitoring for abnormal TLS traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check picotls version/git commit; if before 9b88159ce763d680e4a13b6e8f3171ae923a535d, vulnerable.Check Version:
Check picotls source or linked library version; for git: git log --oneline | grep 9b88159Verify Fix Applied:
Verify picotls includes commit 9b88159ce763d680e4a13b6e8f3171ae923a535d and applications are rebuilt.📡 Detection & Monitoring
Log Indicators:
- Process crashes/aborts related to malloc corruption
- Unexpected termination of TLS services
Network Indicators:
- Malformed TLS handshake messages
- Unusual TLS connection patterns
SIEM Query:
Process termination events with malloc/corruption error codes from TLS services