CVE-2026-63380

Libevent is an event notification library. Prior to 2.2.2-alpha, libevent can dereference invalid list pointers in ws.c when evws_new_session enters its error path after evhttp_start_ws_ succeeds but bufferevent_enable_locking_ fails. evws_connection_free sees a non-null http_server and unconditionally calls TAILQ_REMOVE even though the session was never inserted into http_server->ws_sessions. A local caller able to induce this allocation or locking failure can crash the process. This issue is fixed in version 2.2.2-alpha.

CVSS

No CVSS.

References

Link	Resource
https://github.com/libevent/libevent/commit/825c18bd99f556b59d61200523237f264d5cc734
https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
https://github.com/libevent/libevent/security/advisories/GHSA-3rpf-frgx-xq34
https://github.com/libevent/libevent/security/advisories/GHSA-3rpf-frgx-xq34

Configurations

No configuration.

History

26 Oct 2026, 10:10

Type	Values Removed	Values Added
Summary		(es) Libevent es una biblioteca de notificación de eventos. Anterior a 2.2.2-alpha, libevent puede desreferenciar punteros de lista inválidos en ws.c cuando evws_new_session entra en su ruta de error después de que evhttp_start_ws_ tiene éxito pero bufferevent_enable_locking_ falla. evws_connection_free ve un http_server no nulo y llama incondicionalmente a TAILQ_REMOVE aunque la sesión nunca fue insertada en http_server -> ws_sessions. Un llamador local capaz de inducir este fallo de asignación o bloqueo puede bloquear el proceso. Este problema está solucionado en la versión 2.2.2-alpha.

Information

Published : 2026-08-20 18:16

Updated : 2026-10-26 10:10

NVD link : CVE-2026-63380

Mitre link : CVE-2026-63380

CVE.ORG link : CVE-2026-63380

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

CWE-476

NULL Pointer Dereference

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