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CVE-2026-64555

Full vulnerability record from the local CVENow database.

Description

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.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-27 21:17:08.580000
Last modified
2026-11-03 18:15:39.353000
View original CVE JSON
{
  "id": "CVE-2026-64555",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-27T21:17:08.580",
  "lastModified": "2026-11-03T18:15:39.353",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: nv: Fix SPSR_EL2 restore in kvm_hyp_handle_mops()\n\nkvm_hyp_handle_mops() resets the single-step state machine as part of\nrewinding state for a MOPS exception by modifying vcpu_cpsr() and\nwriting the result directly into hardware.\n\nIn the case of nested virtualization, vcpu_cpsr() is a synthetic value\nsuch that the rest of KVM can deal with vEL2 cleanly. That means the\nvalue requires translation before being written into hardware, which is\nunfortunately missing from the MOPS handler.\n\nFix it by directly modifying SPSR_EL2 and avoiding the synthetic state\naltogether, which will be resynchronized on the next 'full' exit back\nto KVM."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "arch/arm64/kvm/hyp/include/hyp/switch.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2de451a329cf662beeba71f63c7f83ee24ca6642",
              "lessThan": "10a568010e827108d149779908850afaec898846",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2de451a329cf662beeba71f63c7f83ee24ca6642",
              "lessThan": "884b44256041ec6b2dcbe8e6a67384d26145cba1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2de451a329cf662beeba71f63c7f83ee24ca6642",
              "lessThan": "dd3b237eb7780d65eae296d3d3a70012b6e7a02f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2de451a329cf662beeba71f63c7f83ee24ca6642",
              "lessThan": "ff1022c3de46753eb7eba2f6efd990569e66ff95",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "arch/arm64/kvm/hyp/include/hyp/switch.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.7",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.7",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.97",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.40",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.5",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.0,
        "impactScore": 6.0
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/10a568010e827108d149779908850afaec898846",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/884b44256041ec6b2dcbe8e6a67384d26145cba1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/dd3b237eb7780d65eae296d3d3a70012b6e7a02f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ff1022c3de46753eb7eba2f6efd990569e66ff95",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}