CVE-2026-80665 KVM: arm64: nv: Inject SEA if kvm_translate_vncr() can't resolve PFN
A flaw in Linux kernel KVM arm64 nested virtualization allows a guest to trigger a host crash by causing a page fault that isn't properly handled.
- 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-2026-80665?
CVE-2026-80665 is a high-severity denial of service 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:
KVM: arm64: nv: Inject SEA if kvm_translate_vncr() can't resolve PFN
kvm_handle_vncr_abort() assumes that s1_walk_result conveys an abort when kvm_translate_vncr() returns -EFAULT. This is not always the case as it's possible to encounter 'late' failures on the output of S1 translation, e.g. a GFN outside of the memslots.
Fix it by preparing an external abort before returning from kvm_translate_vncr(). Get rid of the BUG_ON() in the fault injection path while at it.
Which versions are affected by CVE-2026-80665?
How do I fix CVE-2026-80665?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-80665 being exploited?
There is no known exploitation of CVE-2026-80665 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80665, DEBIAN-CVE-2026-80665, GHSA-qpmv-4rfj-75x9, UBUNTU-CVE-2026-80665.