CVE-2026-5121

Name	CVE-2026-5121
Description	A flaw was found in libarchive. On 32-bit systems, an integer overflow vulnerability exists in the zisofs block pointer allocation logic. A remote attacker can exploit this by providing a specially crafted ISO9660 image, which can lead to a heap buffer overflow. This could potentially allow for arbitrary code execution on the affected system.
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	1133002

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libarchive (PTS)	bullseye	3.4.3-2+deb11u1	vulnerable
	bullseye (security)	3.4.3-2+deb11u3	vulnerable
	bookworm	3.6.2-1+deb12u3	vulnerable
	bookworm (security)	3.6.2-1+deb12u2	vulnerable
	trixie	3.7.4-4	vulnerable
	forky	3.8.5-1	vulnerable
	sid	3.8.6-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libarchive	source	(unstable)	3.8.7-1			1133002

Notes

[trixie] - libarchive <no-dsa> (Minor issue)
[bookworm] - libarchive <no-dsa> (Minor issue)
https://github.com/libarchive/libarchive/pull/2934
https://github.com/libarchive/libarchive/commit/071e2e1c5981372d40482995ba83c98c8b595418