SB20260912404 - Out-of-bounds write in Linux kernel md dm-pcache driver

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-80962)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a local privileged user to perform out-of-bounds reads and writes.

The vulnerability exists due to out-of-bounds access in the dm-pcache cache metadata handling functions cache_segs_init() and get_seg_id() when loading a cache device with crafted on-disk cache metadata. A local privileged user can supply cache metadata containing an oversized segment count or an out-of-range segment identifier to perform out-of-bounds reads and writes.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/32d1809da31094ef76fd98dc1f1a8b55ca1295dd
• https://git.kernel.org/stable/c/3e19172089ec81132a8a48e802b1034a744209f4
• https://git.kernel.org/stable/c/ab5dcde6fa96bc115b85f3621c60e39c66229a90