Vulnerability in Linux

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.

EPSS: 0.001 (2.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

  • Linux — versions 2de451a329cf662beeba71f63c7f83ee24ca6642, 7.2, 6.18.40

References

Frequently asked questions

What is CVE-2026-64555?
CVE-2026-64555 is a high-severity vulnerability in Linux. CVSS score: 8.8/10. Published 2026-07-27.
How severe is CVE-2026-64555?
High severity. CVSS v3 base score is 8.8 out of 10.