CVE-2026-64555

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: nv: Fix SPSR_EL2 restore in kvm_hyp_handle_mops() kvm_hyp_handle_mops() resets the single-step state machine as part of rewinding state for a MOPS exception by modifying vcpu_cpsr() and writing the result directly into hardware. In the case of nested virtualization, vcpu_cpsr() is a synthetic value such that the rest of KVM can deal with vEL2 cleanly. That means the value requires translation before being written into hardware, which is unfortunately missing from the MOPS handler. Fix it by directly modifying SPSR_EL2 and avoiding the synthetic state altogether, which will be resynchronized on the next 'full' exit back to KVM.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/10a568010e827108d149779908850afaec898846
https://git.kernel.org/stable/c/884b44256041ec6b2dcbe8e6a67384d26145cba1
https://git.kernel.org/stable/c/dd3b237eb7780d65eae296d3d3a70012b6e7a02f
https://git.kernel.org/stable/c/ff1022c3de46753eb7eba2f6efd990569e66ff95

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-27 21:17

Updated : 2026-08-17 05:18

NVD link : CVE-2026-64555

Mitre link : CVE-2026-64555

CVE.ORG link : CVE-2026-64555

JSON object : View

Products Affected

No product.

CWE

No CWE.

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