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CVE-2026-46317

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Reassign nested_mmus array behind mmu_lock kvm->arch.nested_mmus[] is walked under kvm->mmu_lock, including from the MMU notifier path (kvm_unmap_gfn_range() -> kvm_nested_s2_unmap()), which can run at any time. kvm_vcpu_init_nested() reallocates the array and frees the old buffer while holding only kvm->arch.config_lock, so such a walker can reference the freed array. Allocate the new array outside of mmu_lock, as the allocation can sleep. Under the lock, copy the existing entries, fix up the back pointers and reassign the array. Free the old buffer after dropping the lock, as kvfree() can sleep as well.

Severity
HIGH
CVSS score
8.8 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-09 13:16:37
Last modified
2026-10-19 20:18:42.400000
View original CVE JSON 
{
  "id": "CVE-2026-46317",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-06-09T13:16:37.000",
  "lastModified": "2026-10-19T20:18:42.400",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Reassign nested_mmus array behind mmu_lock\n\nkvm->arch.nested_mmus[] is walked under kvm->mmu_lock, including from the\nMMU notifier path (kvm_unmap_gfn_range() -> kvm_nested_s2_unmap()), which\ncan run at any time. kvm_vcpu_init_nested() reallocates the array and frees\nthe old buffer while holding only kvm->arch.config_lock, so such a walker\ncan reference the freed array.\n\nAllocate the new array outside of mmu_lock, as the allocation can sleep.\nUnder the lock, copy the existing entries, fix up the back pointers and\nreassign the array. Free the old buffer after dropping the lock, as\nkvfree() can sleep as well."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nKVM: arm64: Reasignar el array nested_mmus detrás de mmu_lock\n\nkvm->arch.nested_mmus[] es recorrido bajo kvm->mmu_lock, incluyendo desde la ruta del notificador de MMU (kvm_unmap_gfn_range() -> kvm_nested_s2_unmap()), que puede ejecutarse en cualquier momento. kvm_vcpu_init_nested() reasigna el array y libera el búfer antiguo mientras mantiene solo kvm->arch.config_lock, por lo que dicho recorredor puede referenciar el array liberado.\n\nAsignar el nuevo array fuera de mmu_lock, ya que la asignación puede dormir. Bajo el bloqueo, copiar las entradas existentes, corregir los punteros inversos y reasignar el array. Liberar el búfer antiguo después de soltar el bloqueo, ya que kvfree() también puede dormir."
    }
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  "affected": [
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      "affectedData": [
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          "product": "Linux",
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              "versionType": "original_commit_for_fix",
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  ],
  "metrics": {
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        "cvssData": {
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          "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",
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        "ssvcData": {
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Primary",
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  "configurations": [
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}