CVE-2026-80686 mm: migrate_device: fix pte_pfn/pte_dirty called on non-present PTE
A local attacker can trigger a kernel crash or incorrect memory accounting by exploiting undefined behavior in device memory migration code.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80686?
CVE-2026-80686 is a vulnerability in Linux, published on 28 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
mm: migrate_device: fix pte_pfn/pte_dirty called on non-present PTE
pte_pfn() and pte_dirty() have undefined behaviour when called on a non-present PTE. In migrate_vma_collect_pmd(), these functions may be invoked on non-present entries (e.g., device-private entries), leading to potential crashes from pte_pfn() or incorrect dirty folio accounting from pte_dirty(). Fix both by guarding with pte_present() checks.
Which versions are affected by CVE-2026-80686?
How do I fix CVE-2026-80686?
Apply the vendor's patch.
Is CVE-2026-80686 being exploited?
There is no known exploitation of CVE-2026-80686 in the wild and no public exploit code.
Sources
Also known as AZL-98147, BELL-CVE-2026-80686, DEBIAN-CVE-2026-80686, GHSA-m9fp-2x7c-5r66, UBUNTU-CVE-2026-80686.