---
id: CVE-2026-64287
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU

  flush_hyp_vcpu() copies the host vGIC state into the hyp's private vCPU
  on every run
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU

  flush_hyp_vcpu() copies the host vGIC state into the hyp's private vCPU
  on every run. The vGIC list register…
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H'
published: '2026-07-25'
updated: '2026-07-27'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64287'
references:
  - url: 'https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/7fca3fcef81c713bc82a37bf741e0f28e6d04a6f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8cc8bbbfab14c22c5551d0dd19b208a44b141c76'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9fa301d8298778dd799fa4dcf7a7f440715d146e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c646431865f4b1a5b14067233fa27b11e05e0d46'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64287.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-64287'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2507129'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-64287'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64287'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026072503-CVE-2026-64287-ea42@gregkh/T
  - url: 'https://access.redhat.com/errata/RHSA-2026:64808'
  - url: 'https://access.redhat.com/errata/RHSA-2026:64775'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00175
epssPercentile: 0.06124
ingestedAt: '2026-07-27T06:16:50.117Z'
vendor: Red Hat
product: Red Hat Enterprise Linux BaseOS (v. 9)
affected:
  - enterprise_linux 10
  - enterprise_linux 8
  - enterprise_linux 9
  - enterprise_linux_appstream_v_9
  - enterprise_linux_baseos_v_9
  - enterprise_linux_codeready_linux_builder_v_9
  - enterprise_linux_real_time_for_nfv_v_9
  - enterprise_linux_real_time_v_9
patched:
  - enterprise_linux_appstream_v_9
  - enterprise_linux_baseos_v_9
  - enterprise_linux_codeready_linux_builder_v_9
  - enterprise_linux_real_time_for_nfv_v_9
  - enterprise_linux_real_time_v_9
cwe:
  - CWE-125
scores:
  nvd: 8.2
  vendor: 7
---

## Overview

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

KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU

flush_hyp_vcpu() copies the host vGIC state into the hyp's private vCPU
on every run. The vGIC list register save and restore use used_lrs as
their loop bound and expect it to stay within the number of implemented
list registers. While this is generally the case, flush_hyp_vcpu()
copies vgic_v3 verbatim and does not enforce this, so a value provided
by the host is used at EL2 to index vgic_lr[] and access ICH_LR<n>_EL2
(host -> EL2).

Fix by clamping used_lrs to the number of implemented list registers
after the copy, as the trusted path already does in
vgic_flush_lr_state(). The number of implemented list registers is
constant after init, so it is replicated once from
kvm_vgic_global_state.nr_lr into hyp_gicv3_nr_lr rather than read on
every entry.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:64808** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:64808)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64287.json)
- **RHSA-2026:64775** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10), Red Hat Enterprise Linux Real Time for NFV (v. 10), Red Hat Enterprise Linux Real Time (v. 10) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:64775)