CVE-2026-72278

Received Received - Intake

KVM VNCR Abort Re-translation in Linux Kernel

Publication date: 2026-08-15

Last updated on: 2026-08-17

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Re-translate VNCR before injecting abort KVM faults in the VNCR page with FOLL_WRITE whenever the guest aborts for a write, similar to how a regular stage-2 mapping is handled. It is entirely possible that the guest reads from the VNCR before writing to it, in which case the PFN could only be read-only. Invalidate the VNCR TLB and re-fetch the translation upon taking a VNCR abort, allowing the host mapping to be faulted in for write the second time around. Interestingly enough, this also satisfies the ordering requirements of FEAT_ETS2/3 between descriptor updates and MMU faults.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-15

Last Modified

2026-08-17

Generated

2026-09-04

AI Q&A

2026-08-15

EPSS Evaluated

2026-09-03

NVD

CVE-2026-72278

EUVD

EUVD-2026-59177

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This is a vulnerability in the Linux kernel affecting KVM for arm64 systems. It involves a flaw in handling faults in the VNCR page when a guest aborts for a write operation. The issue occurs because the guest might read from the VNCR before writing, leading to a read-only PFN mapping. The fix ensures the VNCR TLB is invalidated and re-translated upon a VNCR abort, allowing proper write access and meeting FEAT_ETS2/3 ordering requirements.

Detection Guidance

This vulnerability is specific to the Linux kernel's KVM implementation for arm64 systems. Detection requires checking the kernel version and KVM configuration. Use uname -a to verify the kernel version and grep for KVM modules with lsmod | grep kvm. If the system is running a vulnerable kernel, update immediately.

Impact Analysis

This vulnerability could allow a guest VM to cause a denial of service or potentially escalate privileges within the host system. It may also lead to unexpected behavior in virtualized environments using KVM on arm64, affecting system stability and security.

Compliance Impact

This vulnerability does not directly affect compliance with GDPR, HIPAA, or similar standards as it pertains to a specific KVM implementation issue in the Linux kernel without clear implications for data protection or privacy.

Mitigation Strategies

Immediately update the Linux kernel to the latest stable version provided by your distribution. Reboot the system to apply the patch. If using KVM for arm64, ensure the hypervisor is updated and configured correctly to avoid VNCR-related faults.

Hi! I’m here to help you understand CVE-2026-72278. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70