CVE-2025-61684

HIGH

Quicly < 2026-01-18 - Denial of Service via Reachable Assertion

Title source: llm

Description

Quicly, an IETF QUIC protocol implementation, is susceptible to a denial-of-service attack prior to commit d9d3df6a8530a102b57d840e39b0311ce5c9e14e. A remote attacker can exploit these bugs to trigger an assertion failure that crashes process using Quicly. Commit d9d3df6a8530a102b57d840e39b0311ce5c9e14e fixes the issue.

References (2)

Core 2

Core References

Vendor Advisory x_refsource_confirm

https://github.com/h2o/quicly/security/advisories/GHSA-wr3c-345m-43v9

Patch x_refsource_misc

https://github.com/h2o/quicly/commit/d9d3df6a8530a102b57d840e39b0311ce5c9e14e

View Patch ZIP pw:eip

Scores

CVSS v3 7.5

EPSS 0.0033

EPSS Percentile 24.8%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment

Exploitation none

Automatable yes

Technical Impact partial

Details

CWE

CWE-617 CWE-20

Status published

Products (1)

h2o/quicly < 2026-01-18

Published Jan 19, 2026

Tracked Since Feb 18, 2026