CVE intelligence

CVE-2026-89916

Vulnerability intelligence

Published Sep 16, 2026Sources checked Oct 21, 2026

9.3CRITICALCVSS out of 10

What this means

Review the available evidence

CVE-2026-89916 and is rated Critical severity with a CVSS score of 9.3. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-89916?

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

KVM: arm64: Make VNCR invalidation participate in MMU invalidation retry

A VNCR TLB invalidation can occur on one vcpu while another vcpu is faulting in this same page. Without correctly handling this, we can end up with the following scenario:

- vcpu A walks the PTs to translate VNCR - before vcpu A is able to grab the MMU lock to insert the TLB, vcpu B updates the S1 PTs with an invalid entry, and issues a TLBI S1E2 for this VA - vcpu A inserts the TLB for something that is now invalid

This isn't a new problem, and we manage S2 by having the MMU notifier to bump up mmu_invalidate_seq on invalidation so that the fault can be replayed.

We can perform something similar here, and extend invalidate_vncr_va() to update the same counter, clearly indicating that the context has changed under our feet. This is safe as the invalidation always happen while holding the MMU lock for write, and that we sample the sequence number before walking S1.

Source: NVD