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.
References5
- github.com/util-linux/util-linux/commit/05c2dbadf34cc74192287f3…
- github.com/util-linux/util-linux/commit/a2d858176b609ab5b853502…
- github.com/util-linux/util-linux/commit/e9d544d013267ea86b70ee8…
- github.com/util-linux/util-linux/releases/tag/v2.41.4
- github.com/util-linux/util-linux/security/advisories/GHSA-h4rw-…
Metrics
- CVSS 3.1
-
8.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 11 November 2026
- CWE
- CWE-190
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