CVE-2026-53615

Name	CVE-2026-53615
Description	util-linux is a random collection of Linux utilities. Before util-linux 2.41.4, `parse_dos_extended()` in `libblkid/src/partitions/dos.c` computes an extended-partition start sector with 32-bit addition and does not apply the extended-area bounds checks to the first two EBR entries. A local attacker who causes a crafted DOS extended-partition disk image or removable medium to be probed can wrap `cur_start + start` to sector zero and cause libblkid to report a false partition overlapping the MBR. This directly compromises the integrity of the reported partition metadata; disk modification or availability loss requires a separate downstream consumer to act on that metadata. This issue is fixed in 2.41.4.
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	1140197

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
util-linux (PTS)	bookworm	2.38.1-5+deb12u3	vulnerable
	bookworm (security)	2.38.1-5+deb12u1	vulnerable
	trixie (security), trixie	2.41.5-0+deb13u1	fixed
	forky, sid	2.42.4-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
util-linux	source	trixie	2.41.5-0+deb13u1
util-linux	source	(unstable)	2.42-1			1140197

Notes

https://github.com/util-linux/util-linux/security/advisories/GHSA-h4rw-gv36-wmp5
Fixed by: https://github.com/util-linux/util-linux/commit/a2d858176b609ab5b8535021a3af9cd302d23d31 (v2.42)
Fixed by: https://github.com/util-linux/util-linux/commit/05c2dbadf34cc74192287f377904afaaf4061623 (v2.41.4)