SB20260828145 - Out-of-bounds write in Linux kernel ocfs2

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-80638)

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

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 an out-of-bounds write in ocfs2_remove_refcount_extent() when unlinking a refcounted file whose refcount tree has leaf blocks. A local user can trigger the vulnerable code path to cause a denial of service.

The issue is detected by a fortify panic when the last leaf block is removed from a refcount tree and the root is converted back to leaf mode.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/1ec3cca2d8b6b9ff6584ca626d4c8918bbf48d44
• https://git.kernel.org/stable/c/f5255516ec7add3a6d5d37853ad5a9a9ddb14305