CVE-2026-13595: kernel util-linux Use After Free

Vulnerability summary

CVE-2026-13595 is a medium (CVSS 6.8) Use After Free vulnerability in kernel util-linux. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.8% of scored vulnerabilities.

Timeline

1. 29-06-2026
   PublishedVulnerability first disclosed.
2. 31-08-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in the libblkid library of util-linux. During nested partition probing, the BSD, Minix, Solaris x86, and UnixWare partition probers cache a raw pointer to a parent partition entry in a dynamically allocated array. When subsequent partition additions cause the array to be reallocated, this pointer becomes stale, leading to a heap use-after-free read. An attacker who can present a crafted block device image (for example, via USB insertion or a loop-mounted disk image) can trigger this flaw without user interaction, as libblkid is invoked automatically by udev/udisks as root on block-device hot-plug events. This could lead to limited information disclosure or denial of service.

• CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.