CVE-2026-18938

Name	CVE-2026-18938
Description	A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.
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)
Debian Bugs	1144476

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
p11-kit (PTS)	bullseye	0.23.22-1	vulnerable
	bookworm	0.24.1-2	vulnerable
	trixie	0.25.5-3	vulnerable
	forky, sid	0.26.5-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
p11-kit	source	(unstable)	0.26.5-1			1144476

Notes

[trixie] - p11-kit <no-dsa> (Minor issue)
https://github.com/p11-glue/p11-kit/pull/777
Fixed by: https://github.com/p11-glue/p11-kit/commit/3e64244e538550c6a7fcf826fa8c50a4604416dc (0.26.5)