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.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
References 5
https://github.com/util-linux/util-linux/commit/05c2dbadf34cc74192287f377904afa…
security-advisories@github.com
https://github.com/util-linux/util-linux/commit/a2d858176b609ab5b8535021a3af9cd…
security-advisories@github.com
https://github.com/util-linux/util-linux/commit/e9d544d013267ea86b70ee8ff78abd2…
security-advisories@github.com
https://github.com/util-linux/util-linux/releases/tag/v2.41.4
security-advisories@github.com
https://github.com/util-linux/util-linux/security/advisories/GHSA-h4rw-gv36-wmp5
security-advisories@github.com