CVE-2026-23345

A flaw was found in the Linux kernel. When the FEAT_LPA2 feature is enabled on ARM64 systems, the kernel incorrectly handles the PTE_SHARED bits in Graphics Control System (GCS) memory mappings. This misconfiguration can lead to a kernel paging request and subsequently a system panic, resulting in a Denial of Service (DoS). A local user or specific system configuration could trigger this vulnerability.

This flaw is specific to ARM64 systems with both FEAT_LPA2 (Large Physical Address 2) and GCS (Guarded Control Stack) enabled. When LPA2 is active, PTE bits 8-9 have a different meaning than shareability, causing incorrect address translation for GCS mappings. This is an uncommon hardware configuration combination, primarily affecting newer ARM platforms.

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.