CVE-2023-42805 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in quinn-proto. O3 Security confirms whether CVE-2023-42805 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
quinn-proto Denial of Service vulnerability
Real-World Exposure
quinn-protoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
quinn-proto is a state machine for the QUIC transport protocol. Prior to versions 0.9.5 and 0.10.5, receiving unknown QUIC frames in a QUIC packet could result in a panic. The problem has been fixed in 0.9.5 and 0.10.5 maintenance releases.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | quinn-proto | all versions | 0.9.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for quinn-proto. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update quinn-proto to 0.9.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-42805 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2023-42805 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2023-42805. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-42805 in your dependencies?
O3 detects CVE-2023-42805 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.