CVE-2026-53615 util-linux libblkid DOS extended-partition overflow produces invalid partition metadata
A local attacker can craft a disk image to trigger an integer overflow in libblkid, causing invalid partition metadata and potential system instability.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53615?
CVE-2026-53615 is a high-severity vulnerability in util-linux, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Weakness: CWE-190
Which versions are affected by CVE-2026-53615?
How do I fix CVE-2026-53615?
Upgrade to a fixed version.
Is CVE-2026-53615 being exploited?
There is no known exploitation of CVE-2026-53615 in the wild and no public exploit code.
Sources
Also known as AZL-108198, BELL-CVE-2026-53615, DEBIAN-CVE-2026-53615, ECHO-9838-e255-038e, GHSA-h4rw-gv36-wmp5, OESA-2026-4576 and 7 more.