CVE-2026-91142

Name	CVE-2026-91142
Description	A flaw was found in Cockpit. An integer overflow vulnerability in the `do_lastlog()` function, specifically in the offset calculation for `lastlog` entries on ILP32 (Integer, Long, Pointer 32-bit) builds, can be exploited. A low-privileged authenticated user with a specially provisioned large User ID (UID) can cause the computed offset to wrap around. This allows the user to perform unauthorized reads and writes to other users' `lastlog` records, potentially disclosing or altering sensitive login accounting information.
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
cockpit (PTS)	bookworm	287.1-0+deb12u3	vulnerable
	bookworm (security)	287.1-0+deb12u2	vulnerable
	trixie (security), trixie	337-1+deb13u2	vulnerable
	forky, sid	368-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
cockpit	source	(unstable)	368-1

Notes

[trixie] - cockpit <no-dsa> (Minor issue)
https://bugzilla.redhat.com/show_bug.cgi?id=2479459
https://github.com/cockpit-project/cockpit/commit/5efa4af065321873f6eb8988f3b0b50e981689ba (368)
https://github.com/cockpit-project/cockpit/commit/6e76c96272a4ebcb085c948e5cc9189eeee561af (368)