SB2026091928 - Improper initialization in Linux kernel block null_blk driver
Published: September 19, 2026
Security Bulletin ID
SB2026091928
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper initialization (CVE-ID: CVE-2026-90190)
CWE-ID: CWE-665 - Improper Initialization
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger a kernel warning.
The vulnerability exists due to improper initialization of a file-scope mutex in the null_blk driver when creating a configfs directory during null_blk initialization. A local user can race a mkdir operation with mutex initialization to trigger a kernel warning.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/017dac7670909eaea3eb36e6b3b5a8be9ce0a14d
- https://git.kernel.org/stable/c/0a8c2f7b95981913ac370683e34db4906970c210
- https://git.kernel.org/stable/c/234117949da3b3f9705a21b66094f9f30bbe681d
- https://git.kernel.org/stable/c/349903f7ee72f7ac5b7a98840d701b2082d140a3
- https://git.kernel.org/stable/c/c7dea90c9b4ef1dfbd2e4df36de180c76fd7c33c
- https://git.kernel.org/stable/c/f9f4ca45c770b7eec83fea6c9b727b26e691b513