High severity · published Oct 14, 2026
CVE-2026-53615
util-linux libblkid DOS extended-partition overflow produces invalid partition metadata
8.0
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UT
util-linux · util-linux
< 2.41.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53615
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-53615
x_refsource_CONFIRM
https://github.com/util-linux/util-linux/security/advisories/GHSA-h4rw-gv36-wmp5
x_refsource_MISC
https://github.com/util-linux/util-linux/commit/05c2dbadf34cc74192287f377904afaaf4061623
x_refsource_MISC
https://github.com/util-linux/util-linux/commit/a2d858176b609ab5b8535021a3af9cd302d23d31
x_refsource_MISC
https://github.com/util-linux/util-linux/commit/e9d544d013267ea86b70ee8ff78abd280e6641af
x_refsource_MISC
https://github.com/util-linux/util-linux/releases/tag/v2.41.4
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