Vulnerability-Lookup

GHSA-HFCP-QWVJ-9247

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-27 06:30

Details

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.

Severity

8.2 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64287"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:09Z",
    "severity": "HIGH"
  },
  "details": "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\u0027s 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\u003cn\u003e_EL2\n(host -\u003e 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.",
  "id": "GHSA-hfcp-qwvj-9247",
  "modified": "2026-07-27T06:30:31Z",
  "published": "2026-07-25T12:31:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64287"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7fca3fcef81c713bc82a37bf741e0f28e6d04a6f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8cc8bbbfab14c22c5551d0dd19b208a44b141c76"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9fa301d8298778dd799fa4dcf7a7f440715d146e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c646431865f4b1a5b14067233fa27b11e05e0d46"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-64287 (GCVE-0-2026-64287)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-07-27 04:59

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<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

8.2 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Assigner

Linux

References

5 references

URL	Tags
https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa…
https://git.kernel.org/stable/c/9fa301d8298778dd7…
https://git.kernel.org/stable/c/c646431865f4b1a5b…
https://git.kernel.org/stable/c/7fca3fcef81c713bc…
https://git.kernel.org/stable/c/8cc8bbbfab14c22c5…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8 (git) Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 9fa301d8298778dd799fa4dcf7a7f440715d146e (git) Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < c646431865f4b1a5b14067233fa27b11e05e0d46 (git) Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 7fca3fcef81c713bc82a37bf741e0f28e6d04a6f (git) Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 8cc8bbbfab14c22c5551d0dd19b208a44b141c76 (git)
Linux	Linux	Affected: 6.2 Unaffected: 0 , < 6.2 (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "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",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8",
              "status": "affected",
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "versionType": "git"
            },
            {
              "lessThan": "9fa301d8298778dd799fa4dcf7a7f440715d146e",
              "status": "affected",
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "versionType": "git"
            },
            {
              "lessThan": "c646431865f4b1a5b14067233fa27b11e05e0d46",
              "status": "affected",
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "versionType": "git"
            },
            {
              "lessThan": "7fca3fcef81c713bc82a37bf741e0f28e6d04a6f",
              "status": "affected",
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "versionType": "git"
            },
            {
              "lessThan": "8cc8bbbfab14c22c5551d0dd19b208a44b141c76",
              "status": "affected",
              "version": "be66e67f175096f283c9d5614c4991fc9e7ed975",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "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",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.2"
            },
            {
              "lessThan": "6.2",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "6.2",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.4",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                }
              ],
              "negate": false,
              "operator": "OR"
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      ],
      "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\u0027s 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\u003cn\u003e_EL2\n(host -\u003e 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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-27T04:59:28.711Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8"
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          "url": "https://git.kernel.org/stable/c/9fa301d8298778dd799fa4dcf7a7f440715d146e"
        },
        {
          "url": "https://git.kernel.org/stable/c/c646431865f4b1a5b14067233fa27b11e05e0d46"
        },
        {
          "url": "https://git.kernel.org/stable/c/7fca3fcef81c713bc82a37bf741e0f28e6d04a6f"
        },
        {
          "url": "https://git.kernel.org/stable/c/8cc8bbbfab14c22c5551d0dd19b208a44b141c76"
        }
      ],
      "title": "KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64287",
    "datePublished": "2026-07-25T08:49:28.168Z",
    "dateReserved": "2026-07-19T15:36:31.778Z",
    "dateUpdated": "2026-07-27T04:59:28.711Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-HFCP-QWVJ-9247

CVE-2026-64287 (GCVE-0-2026-64287)

Tags

Sightings

Nomenclature