CVE-2026-63381

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero. evbuffer_free_all_chains frees the initial empty chain without resetting outbuf->first, outbuf->last, or outbuf->last_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer. A caller that can drive this buffer state can cause memory corruption or a process crash. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

CVSS

No CVSS.

References

Link	Resource
https://github.com/libevent/libevent/commit/5cb95ba2f804f8aff46f88d58391c71e1251cd1c
https://github.com/libevent/libevent/commit/9db091b04f569be3a700fa9860ef02f90b830af9
https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable
https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
https://github.com/libevent/libevent/security/advisories/GHSA-c2pj-cg4r-88c8

Configurations

No configuration.

History

26 Oct 2026, 10:10

Type	Values Removed	Values Added
Summary		(es) Libevent es una biblioteca de notificación de eventos. Antes de las versiones 2.1.13 y 2.2.2-alpha, libevent tiene un uso después de liberación en buffer.c cuando evbuffer_add_buffer_reference procesa un búfer de salida cuyo out_total_len es cero. evbuffer_free_all_chains libera la cadena vacía inicial sin restablecer outbuf -> first, outbuf -> last, o outbuf -> last_with_datap, y APPEND_CHAIN_MULTICAST posteriormente desreferencia el puntero de cadena colgante. Un llamador que puede impulsar este estado del búfer puede causar corrupción de memoria o un fallo del proceso. Este problema está solucionado en las versiones 2.1.13 y 2.2.2-alpha.

Information

Published : 2026-08-20 18:16

Updated : 2026-10-26 10:10

NVD link : CVE-2026-63381

Mitre link : CVE-2026-63381

CVE.ORG link : CVE-2026-63381

JSON object : View

Products Affected

No product.

CWE

CWE-908

Use of Uninitialized Resource

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