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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63381 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 5.8 MEDIUM
Vector:  CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/libevent/libevent/commit/5cb95ba2f804f8aff46f88d58391c71e1251cd1c GitHub, Inc.
https://github.com/libevent/libevent/commit/9db091b04f569be3a700fa9860ef02f90b830af9 GitHub, Inc.
https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable GitHub, Inc.
https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha GitHub, Inc.
https://github.com/libevent/libevent/security/advisories/GHSA-c2pj-cg4r-88c8 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-908 Use of Uninitialized Resource GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63381
NVD Published Date:
08/20/2026
NVD Last Modified:
08/20/2026
Source:
GitHub, Inc.