CVE-2023-53205: Linux Kernel

High severity, CVSS 7.8. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: KVM: s390/diag: fix racy access of physical cpu number in diag 9c handler We do check for target CPU == -1, but this might change at the time we are going to use it. Hold the physical target CPU in a local variable to avoid out-of-bound accesses to the cpu arrays.

Affected products

• Linux Linux Kernel: from 5.13, before 5.15.121 (fixed in 5.15.121); from 5.16, before 6.1.39 (fixed in 6.1.39); from 6.2, before 6.4.4 (fixed in 6.4.4)

Published 2025-09-15. Last modified 2026-08-04.