CVE-2025-61684

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/h2o/quicly/commit/d9d3df6a8530a102b57d840e39b0311ce5c9e14e	Patch
https://github.com/h2o/quicly/security/advisories/GHSA-wr3c-345m-43v9	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:h2o:quicly:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-19 16:15

Updated : 2026-02-27 19:41

NVD link : CVE-2025-61684

Mitre link : CVE-2025-61684

CVE.ORG link : CVE-2025-61684

JSON object : View

Products Affected

h2o

quicly

CWE

CWE-20

Improper Input Validation

CWE-617

Reachable Assertion

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