CVE-2026-90009

scsi: bsg: Fix TOCTOU in io_uring passthrough command setup

Published Sep 16, 2026 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
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

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Weaknesses CWE-119
CWE-364
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Type Values Removed Values Added
Description 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.
Title scsi: bsg: Fix TOCTOU in io_uring passthrough command setup
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 19, 2026, 8:56 AM
Reserved
Sep 11, 2026, 7:38 PM
Status
Received
Published
Sep 16, 2026, 11:17 AM
Modified
Oct 19, 2026, 9:18 AM