CVE-2026-22184

Name	CVE-2026-22184
Description	zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz. The vulnerability is limited to the standalone demonstration utility and does not affect the core zlib compression library. The flaw occurs when a user executes the untgz command with an excessively long archive name supplied via the command line, leading to an out-of-bounds write in a fixed-size global buffer.
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
zlib (PTS)	bullseye (security), bullseye	1:1.2.11.dfsg-2+deb11u2	fixed
	bookworm	1:1.2.13.dfsg-1	fixed
	forky, sid, trixie	1:1.3.dfsg+really1.3.1-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
zlib	source	(unstable)	1:1.2.6.dfsg-1	unimportant

Notes

https://www.openwall.com/lists/oss-security/2026/01/06/5
https://github.com/madler/zlib/issues/1142
contrib/untgz excluded from orig tarball since 1:1.2.3.5.dfsg-1
Before the change contrib/untgz not build for Debian