CVE-2024-45396
📋 TL;DR
CVE-2024-45396 is a denial-of-service vulnerability in Quicly, an IETF QUIC protocol implementation. A remote attacker can trigger an assertion failure that crashes any process using vulnerable versions of Quicly. This affects applications and services that depend on Quicly for QUIC protocol functionality.
💻 Affected Systems
- Quicly
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption for applications using Quicly, leading to extended downtime and potential cascading failures in dependent systems.
Likely Case
Intermittent crashes of QUIC-enabled services, causing availability issues and degraded performance for users.
If Mitigated
Minimal impact with proper network segmentation and monitoring, though services remain vulnerable to targeted attacks.
🎯 Exploit Status
The advisory describes remote exploitation triggering assertion failures, suggesting relatively straightforward exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit 2a95896104901589c495bc41460262e64ffcad5c and later
Vendor Advisory: https://github.com/h2o/quicly/security/advisories/GHSA-mp3c-h5gg-mm6p
Restart Required: Yes
Instructions:
1. Update Quicly to commit 2a95896104901589c495bc41460262e64ffcad5c or later. 2. Rebuild applications using Quicly. 3. Restart affected services.
🔧 Temporary Workarounds
Network filtering
allBlock or rate-limit QUIC traffic to vulnerable systems using firewalls or network controls.
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable systems from untrusted networks.
- Deploy monitoring and alerting for process crashes related to Quicly services.
🔍 How to Verify
Check if Vulnerable:
Check Quicly version or commit hash. If using commit d720707 or earlier, system is vulnerable.Check Version:
Check build configuration or source code for Quicly commit hash.Verify Fix Applied:
Verify Quicly is at commit 2a95896104901589c495bc41460262e64ffcad5c or later.📡 Detection & Monitoring
Log Indicators:
- Process crashes of applications using Quicly
- Assertion failure messages in application logs
Network Indicators:
- Unusual QUIC traffic patterns
- Connection resets to QUIC services
SIEM Query:
Process termination events for applications known to use Quicly library