CVE-2026-89966

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An unprivileged user can cause a kernel panic (system crash) by requesting a gigantic hugepage allocation using MPOL PREFERRED MANY on systems where the Contiguous Memory Allocator (CMA) is configured on only a subset of NUMA nodes. The issue occurs because the hugetlb cma alloc frozen folio() function dereferences a nodemask without verifying if it is NULL. This happens when alloc buddy hugetlb folio with mpol() passes a NULL nodemask to alloc fresh hugetlb folio(), which is then propagated through alloc gigantic frozen folio() to the vulnerable function. The crash is triggered during the execution of node isset() and for each node mask() when they attempt to access the NULL nodemask pointer.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.