← Back to CVE Explorer

CVE-2026-64287

Full vulnerability record from the local CVENow database.

Description

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.

Severity
HIGH
CVSS score
8.2 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:09.353000
Last modified
2026-10-19 21:17:29.827000
View original CVE JSON 
{
  "id": "CVE-2026-64287",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:09.353",
  "lastModified": "2026-10-19T21:17:29.827",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU\n\nflush_hyp_vcpu() copies the host vGIC state into the hyp's private vCPU\non every run. The vGIC list register save and restore use used_lrs as\ntheir loop bound and expect it to stay within the number of implemented\nlist registers. While this is generally the case, flush_hyp_vcpu()\ncopies vgic_v3 verbatim and does not enforce this, so a value provided\nby the host is used at EL2 to index vgic_lr[] and access ICH_LR<n>_EL2\n(host -> EL2).\n\nFix by clamping used_lrs to the number of implemented list registers\nafter the copy, as the trusted path already does in\nvgic_flush_lr_state(). The number of implemented list registers is\nconstant after init, so it is replicated once from\nkvm_vgic_global_state.nr_lr into hyp_gicv3_nr_lr rather than read on\nevery entry."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "arch/arm64/include/asm/kvm_hyp.h",
            "arch/arm64/kvm/arm.c",
            "arch/arm64/kvm/hyp/nvhe/hyp-main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "lessThan": "2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "lessThan": "9fa301d8298778dd799fa4dcf7a7f440715d146e",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "lessThan": "c646431865f4b1a5b14067233fa27b11e05e0d46",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "lessThan": "7fca3fcef81c713bc82a37bf741e0f28e6d04a6f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "lessThan": "8cc8bbbfab14c22c5551d0dd19b208a44b141c76",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "arch/arm64/include/asm/kvm_hyp.h",
            "arch/arm64/kvm/arm.c",
            "arch/arm64/kvm/hyp/nvhe/hyp-main.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.2",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.2",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.145",
              "lessThanOrEqual": "6.6.*",
              "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": "7.1.4",
              "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:H/UI:N/S:C/C:H/I:H/A:H",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "HIGH",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.5,
        "impactScore": 6.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:38:27.178822Z",
          "id": "CVE-2026-64287",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-noinfo"
        }
      ]
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.2",
              "versionEndExcluding": "6.6.145",
              "matchCriteriaId": "7046B092-F810-4440-ACE6-60218518EECE"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.7",
              "versionEndExcluding": "6.12.97",
              "matchCriteriaId": "05880CF6-5AD2-44E9-853A-6CE8318E76A5"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.13",
              "versionEndExcluding": "6.18.40",
              "matchCriteriaId": "67D87928-1419-4529-9201-42C059678CB4"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "6.19",
              "versionEndExcluding": "7.1.4",
              "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/7fca3fcef81c713bc82a37bf741e0f28e6d04a6f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/8cc8bbbfab14c22c5551d0dd19b208a44b141c76",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/9fa301d8298778dd799fa4dcf7a7f440715d146e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://git.kernel.org/stable/c/c646431865f4b1a5b14067233fa27b11e05e0d46",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ]
    }
  ]
}