CVE-2026-31397

A flaw was found in the Linux kernel's memory management subsystem, specifically within the move_pages_huge_pmd() function. A local user could exploit a NULL pointer dereference when handling huge zero pages, which can lead to a system crash and a Denial of Service (DoS). Furthermore, improper reconstruction of Page Middle Directory (PMD) entries can cause memory corruption by incorrectly treating special memory mappings as normal pages, potentially leading to system instability.