SB20260626189 - NULL pointer dereference in Linux kernel iomap

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-53165)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

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

The vulnerability exists due to a null pointer dereference race condition in iomap_finish_folio_read() when reporting buffered read errors during concurrent read completion and truncate operations. A local user can trigger a buffered read failure while racing read completion with truncate activity to cause a denial of service.

The issue occurs because the folio can be unlocked and detached before the error reporting path dereferences folio->mapping.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/1ad453817a4077230d1ba88eb0868f05f824449a
• https://git.kernel.org/stable/c/2eea7f44b9c8b42fd7d3a1a87c06a7cd1b99c327