CVE-2026-63383

Name	CVE-2026-63383
Description	Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent can read beyond a contiguous evbuffer region in event_tagging.c when decode_tag_internal requests at most five bytes from evbuffer_pullup but iterates using the full logical buffer length. A fragmented evbuffer containing a six-byte malformed tag can therefore advance past the pullup window and trigger an out-of-bounds read, which can crash a process that decodes attacker-controlled tagged RPC data. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libevent (PTS)	bullseye	2.1.12-stable-1	vulnerable
	bookworm	2.1.12-stable-8	vulnerable
	trixie	2.1.12-stable-10	vulnerable
	forky, sid	2.1.13-stable-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libevent	source	(unstable)	2.1.13-stable-1

Notes

https://github.com/libevent/libevent/security/advisories/GHSA-fj29-64w6-73h6
Fixed by: https://github.com/libevent/libevent/commit/e1f9e21887c6b104e206a718385ba3ffc75180cb (release-2.1.13-stable)
Fixed by: https://github.com/libevent/libevent/commit/91ed8745eebabdd27592a83d350338a8c4626321 (release-2.2.2-alpha)