---
id: CVE-2026-90009
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  scsi: bsg: Fix TOCTOU in io_uring passthrough command setup

  scsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.
  Userspace can change a field after we …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  scsi: bsg: Fix TOCTOU in io_uring passthrough command setup

  scsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.
  Userspace can change a field after we …
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 7b6d3255e7f8c6df2d21504c47808e3ce84649ac <
    f033530105aa73d82c121d54b57f358e4865d2f4
  - >-
    Linux >= 7b6d3255e7f8c6df2d21504c47808e3ce84649ac <
    4b3c5965fca99f62d31c963294bd5b23cc488e97
  - Linux 7.1
published: '2026-09-16'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:18:24.553'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90009'
references:
  - url: 'https://git.kernel.org/stable/c/4b3c5965fca99f62d31c963294bd5b23cc488e97'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f033530105aa73d82c121d54b57f358e4865d2f4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-16T10:53:53.944Z'
epss: 0.00165
epssPercentile: 0.05054
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

scsi: bsg: Fix TOCTOU in io_uring passthrough command setup

scsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.
Userspace can change a field after we check it and before we use it.
request_len is the sharp case: it can grow past sizeof(scmd->cmnd) after
the bound check and overflow scmd->cmnd in copy_from_user().

READ_ONCE() the SQE fields we check or use into locals before use.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.