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

17 Jun 2026, 09:50

Type	Values Removed	Values Added
Summary		(es) Quicly, una implementación del protocolo QUIC de IETF, es susceptible a un ataque de denegación de servicio anterior al commit d9d3df6a8530a102b57d840e39b0311ce5c9e14e. Un atacante remoto puede explotar estos errores para desencadenar un fallo de aserción que bloquea el proceso que usa Quicly. El commit d9d3df6a8530a102b57d840e39b0311ce5c9e14e soluciona el problema.

27 Feb 2026, 19:41

Type	Values Removed	Values Added
CPE		cpe:2.3:a:h2o:quicly::::::::
References	~~() https://github.com/h2o/quicly/commit/d9d3df6a8530a102b57d840e39b0311ce5c9e14e -~~	() https://github.com/h2o/quicly/commit/d9d3df6a8530a102b57d840e39b0311ce5c9e14e - Patch
References	~~() https://github.com/h2o/quicly/security/advisories/GHSA-wr3c-345m-43v9 -~~	() https://github.com/h2o/quicly/security/advisories/GHSA-wr3c-345m-43v9 - Vendor Advisory
CWE		CWE-617
First Time		H2o quicly H2o

19 Jan 2026, 16:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-19 16:15

Updated : 2026-06-17 09:50

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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