SB20260916103 - Time-of-check Time-of-use (TOCTOU) Race Condition in Linux kernel scsi driver

Description

This security bulletin contains information about 1 vulnerability.

1) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2026-90009)

CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service and compromise confidentiality and integrity.

The vulnerability exists due to a time-of-check to time-of-use race condition in scsi_bsg_uring_cmd() when processing io_uring passthrough commands from a shared memory-mapped submission queue entry. A local user can modify the request length after validation to overflow scmd->cmnd during copy_from_user() and cause a denial of service and compromise confidentiality and integrity.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/4b3c5965fca99f62d31c963294bd5b23cc488e97
• https://git.kernel.org/stable/c/f033530105aa73d82c121d54b57f358e4865d2f4