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

Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-08-17 04:52
VLAI
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
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 2c5e72b9fbf83fdfa724e9f1af0f418ccf8739b8 (git)
Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 9fa301d8298778dd799fa4dcf7a7f440715d146e (git)
Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < c646431865f4b1a5b14067233fa27b11e05e0d46 (git)
Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 7fca3fcef81c713bc82a37bf741e0f28e6d04a6f (git)
Affected: be66e67f175096f283c9d5614c4991fc9e7ed975 , < 8cc8bbbfab14c22c5551d0dd19b208a44b141c76 (git)
guessed Create a notification for this product.
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 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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          "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."
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      "title": "KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU",
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      "version": "2"
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    "redhat_vex": {
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      "current_release_date": "2026-09-14T19:49:07+00:00",
      "cve": "CVE-2026-64287",
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      "title": "kernel: KVM: arm64: Bound used_lrs when flushing the pKVM hyp vCPU",
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      "cve": "CVE-2026-64287",
      "id": "CVE-2026-64287",
      "initial_release_date": "2026-07-25T16:46:32Z",
      "product_status:first_fixed": "65",
      "product_status:known_affected": "498",
      "product_status:known_not_affected": "251",
      "product_status:recommended": "129",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64287",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64287.json",
      "version": "11"
    }
  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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