CVE-2026-64558: Linux

High severity, CVSS 7.8. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: s390/pkey: Check length in pkey_pckmo handler implementation Explicitly check the length of the target buffer in the pkey_pckmo implementation of the key_to_protkey() handler function. The handler function fails, if the generated output data exceeds the length of the provided target buffer.

Affected products

• Linux Linux: from 6.12, before 6.12.97 (fixed in 6.12.97); from 6.13, before 6.18.40 (fixed in 6.18.40); from 6.19, before 7.1.5 (fixed in 7.1.5)

Published 2026-07-29. Last modified 2026-08-17.