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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63388 Detail

Description

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a heap out-of-bounds write in bufferevent_sock.c when bufferevent_socket_set_conn_address_ copies a kernel-supplied AF_UNIX peer address into bufferevent_private.conn_address. Release builds compiled with NDEBUG disable the EVUTIL_ASSERT length guard, and the evhttp accept path can pass a 110-byte sockaddr from accept() into the 28-byte field. An unauthenticated local peer able to connect to an AF_UNIX listener can overwrite the adjacent dns_request pointer and heap data, causing memory corruption with confidentiality, integrity, and availability impact. 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.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/libevent/libevent/commit/52057cb33d0c20c0a0453fbabe6c0c96854931b9 GitHub, Inc.
https://github.com/libevent/libevent/commit/ef38f926e9cd1f082416c6fff13587bc1f431d72 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-cvq5-vrvr-j338 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-617 Reachable Assertion GitHub, Inc.  
CWE-787 Out-of-bounds Write GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63388
NVD Published Date:
08/20/2026
NVD Last Modified:
08/20/2026
Source:
GitHub, Inc.