CVE-2026-31812
Denial of service in Quinn endpoints
Description
Quinn is a pure-Rust, async-compatible implementation of the IETF QUIC transport protocol. Prior to 0.11.14, a remote, unauthenticated attacker can trigger a denial of service in applications using vulnerable quinn versions by sending a crafted QUIC Initial packet containing malformed quic_transport_parameters. In quinn-proto parsing logic, attacker-controlled varints are decoded with unwrap(), so truncated encodings cause Err(UnexpectedEnd) and panic. This is reachable over the network with a single packet and no prior trust or authentication. This vulnerability is fixed in 0.11.14.
How to fix CVE-2026-31812
To remediate CVE-2026-31812, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 0.11.14 or later
- —upgrade to 0.11.14 or later
Is CVE-2026-31812 being exploited?
Low — EPSS is 0.5%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0
- from 0, < 0.11.14
- >= 0.5.0, < 0.11.14
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |