CVE-2026-91142
Low CVSS 3.6Published 2026-09-18 ยท last changed 2026-09-18
The fix
We hold no Microsoft remediation data for CVE-2026-91142, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.
What it is
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.
Sources
CVSS vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N