CVE-2023-42805 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in quinn-proto. A fix is available for quinn-proto — see the affected versions and patch details below.
quinn-proto Denial of Service vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-42805.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
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 | 0.9.5cargo update -p quinn-proto --precise 0.9.5 |
Affected Products
quinnquinn_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for quinn-proto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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.
Frequently Asked Questions
Is CVE-2023-42805 in your dependencies?
Find it across crates.io, including transitive dependencies.