SB2026091923 - NULL pointer dereference in Linux kernel block null_blk driver
Published: September 19, 2026
Security Bulletin ID
SB2026091923
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) NULL pointer dereference (CVE-ID: CVE-2026-90186)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local privileged user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in null_blk shared tag set queue-resize handling when resizing submit_queues or poll_queues through configfs on a device with shared_tags enabled. A local privileged user can resize the per-device queue configuration to cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/1cdfe2fa62b48728a9b436fbbd3dbe4c11593e24
- https://git.kernel.org/stable/c/3e35ad503386a2e8a0e0460530dcbf421c79f6f2
- https://git.kernel.org/stable/c/9c7bae099ddc92676ad1b7e29dd6c089e5f6196c
- https://git.kernel.org/stable/c/baff300541a0012907cdde349728739fe16176d7
- https://git.kernel.org/stable/c/f609f7bf9ce8c2fc427705c4a9f623a281239d06
- https://git.kernel.org/stable/c/fcd53f3e8b758c79c3f2420d28a2a1dce6fda61a