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

{
  "id": "ed2b9da87ff464b1af553ca5bda5fb18b306bac11578d4d1b6b766c0dec03291",
  "url": "https://osv.dev/vulnerability/CVE-2026-64287",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU",
    "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 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_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.",
    "evidence": "osv:CVE-2026-64287",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.145",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.97",
            "evidence": "/affected/1/ranges"
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          {
            "value": "6.18.40",
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          {
            "value": "7.1.4",
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        "affected_versions": []
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    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-64287",
      "aliases": [
        "CVE-2026-64287"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H"
        }
      ],
      "affected": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
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                  "fixed": "2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8"
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                  "fixed": "9fa301d8298778dd799fa4dcf7a7f440715d146e"
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                  "fixed": "7fca3fcef81c713bc82a37bf741e0f28e6d04a6f"
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                  "fixed": "8cc8bbbfab14c22c5551d0dd19b208a44b141c76"
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              "type": "ECOSYSTEM",
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                  "introduced": "6.2.0"
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              "type": "ECOSYSTEM",
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                  "introduced": "6.19.0"
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64287.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.638662453Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8",
        "https://git.kernel.org/stable/c/7fca3fcef81c713bc82a37bf741e0f28e6d04a6f",
        "https://git.kernel.org/stable/c/8cc8bbbfab14c22c5551d0dd19b208a44b141c76",
        "https://git.kernel.org/stable/c/9fa301d8298778dd799fa4dcf7a7f440715d146e",
        "https://git.kernel.org/stable/c/c646431865f4b1a5b14067233fa27b11e05e0d46",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64287.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64287",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64287.json"
      }
    },
    "related_cves": [
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        "value": "CVE-2026-64287",
        "evidence": "/id"
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    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 490226,
  "published_at": "2026-07-25T08:49:28.168+00:00"
}