CVE-2026-31482

A flaw was found in the Linux kernel, specifically within the s390 architecture's kernel entry process. Due to an incomplete update, a critical register (r12) was not properly cleared when entering the kernel. This oversight could allow a local user to potentially access sensitive system information, such as the current task pointer, which should not be exposed.

Upstream restored register scrubbing for %r12 on s390 kernel entry after branch-prediction macro cleanup removed the implicit load. Red Hat agrees this is a defense-in-depth fix against unintended kernel pointer leakage to user-controlled speculation gadgets on s390. Ship via architecture-specific kernel builds.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.