SB20260912331 - NULL pointer dereference in Linux kernel s390 block driver
Published: September 12, 2026
Security Bulletin ID
SB20260912331
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-2026-89457)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in s390 DASD sysfs discipline callbacks when reading world-readable sysfs attributes during device initialization. A local user can read a sysfs attribute before private device data is allocated to trigger a kernel panic and cause a denial of service.
Remediation
Install update from vendor's website.