SB2026091803 - Infinite loop in Linux kernel md dm-pcache driver

Description

This security bulletin contains information about 1 vulnerability.

1) Infinite loop (CVE-ID: CVE-2026-93198)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper validation of a persisted dirty_tail chain in the dm-pcache cache loader when loading a crafted cache image. A local user can provide a crafted cache image containing a nonterminating last-kset chain to cause a denial of service.

The persisted on-media fields are authenticated only by a crc32c with a fixed seed.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/4822a030929e0e77aa380722dc42e3e4c9edd346
• https://git.kernel.org/stable/c/58d620ee9e01d4bdbceaf2ae1450d307a2a9d58b
• https://git.kernel.org/stable/c/8195cf3f4a82ef49d9b0651c507ed0784caf23fb