SB2026091703 - Incorrect calculation in Linux kernel s390 crypto driver
Published: September 17, 2026
Security Bulletin ID
SB2026091703
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Incorrect calculation (CVE-ID: CVE-2026-89959)
CWE-ID: CWE-682 - Incorrect Calculation
CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to compromise the confidentiality, integrity, and availability of a KVM guest.
The vulnerability exists due to an incorrect bitmap operation in vfio_ap_mdev_cfg_remove when removing control domains from a mediated device. A local user can trigger control-domain removal to compromise the confidentiality, integrity, and availability of a KVM guest.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/02e72909453dee2f8a09f78819f9a9cb902dfbdc
- https://git.kernel.org/stable/c/12871a4269f139221c9fde9ea3eb69c9228f59d4
- https://git.kernel.org/stable/c/2ff68bf414de167bc138e6e211ee1ad3ab3c5052
- https://git.kernel.org/stable/c/4bffadde7fc49b00493fb78c6376f958998d4b8c
- https://git.kernel.org/stable/c/6b8a02e216f6b520cc029e43ddc83956605135d5
- https://git.kernel.org/stable/c/f7d66afc34bc6e833c8ebe56973afec35f473bc1