SB20260918345 - Improper input validation in Linux kernel block driver
Published: September 18, 2026
Security Bulletin ID
SB20260918345
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Partial DoS
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper input validation (CVE-ID: CVE-2026-90323)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper input validation in the UBLK io_uring command handling when processing automatic buffer registration data from a submission queue entry. A local user can submit an io_uring command with invalid automatic buffer registration data to cause a teardown hang.
Remediation
Install update from vendor's website.