CVE-2026-68172

Technical Description

In the Linux kernel, the following vulnerability has been resolved:

arm64: make huge_ptep_get handled unaligned addresses

huge_ptep_get() can be handed a virtual address pointing to the middle

of a contpmd/contpte mapped hugetlb folio (examples of callers are

pagemap_hugetlb_range, page_mapped_in_vma).

The arm64 helper rewalks the pgtables in find_num_contig to answer

whether the huge pte we have maps a contpmd or a contpte hugetlb folio,

and returns CONT_PMDS or CONT_PTES, so that it can collect a/d bits over

the contiguous ptes. We can falsely return CONT_PTES instead of

CONT_PMDS if the addr is not aligned. On systems where CONT_PTES !=

CONT_PMDS (meaning page size is 16K), we could collect excess A/D bit

state, meaning extra work for the kernel. Even worse, we may iterate

beyond the PTE table and dereference a garbage ptep pointer to access

physical memory we don't own. Since the ptep pointer is a linear map

address, we may run off the end of the linear map or into a hole,

deref

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References