CVE-2026-89918

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Correctly handle end of VA space TLBI invalidation Our TLB invalidation by VA code is based on comparing two ranges, one defined by the TLB, and one defined by the TLBI instruction. Each range is defined by a start and a size. However, the way the comparison is done doesn't account for address rollover, as it compares an address with (base + size). This works nicely until this expression represent the last page/block in the TTBR1 VA space, as the result is a big fat 0. And a failed TLB invalidation. Rewrite the comparison in a way that is immune to the address rollover (making the end address inclusive instead of exclusive), and move this into a common helper that is used by both VA and IPA invalidations, as suggested by Hyunwoo Kim (although the IPA version didn't suffer from this particular problem, obviously).

Severity

CRITICAL

CVSS score

9.3 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-09-16 11:17:00.867000

Last modified

2026-10-19 09:18:37.293000

View original CVE JSON

{
  "id": "CVE-2026-89918",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:17:00.867",
  "lastModified": "2026-10-19T09:18:37.293",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Correctly handle end of VA space TLBI invalidation\n\nOur TLB invalidation by VA code is based on comparing two ranges,\none defined by the TLB, and one defined by the TLBI instruction.\n\nEach range is defined by a start and a size. However, the way the\ncomparison is done doesn't account for address rollover, as it\ncompares an address with (base + size). This works nicely until\nthis expression represent the last page/block in the TTBR1 VA space,\nas the result is a big fat 0. And a failed TLB invalidation.\n\nRewrite the comparison in a way that is immune to the address\nrollover (making the end address inclusive instead of exclusive),\nand move this into a common helper that is used by both VA and IPA\ninvalidations, as suggested by Hyunwoo Kim (although the IPA version\ndidn't suffer from this particular problem, obviously)."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "arch/arm64/kvm/nested.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "lessThan": "ce447651a52ec077694172af10c4fffb11f56c43",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "lessThan": "c624731ca6fe59ad8909ce4108301aa7560a91d6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "lessThan": "34af2c3e31f91a739dc175459fdbd99ed952b457",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "arch/arm64/kvm/nested.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.16",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.16",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "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:N/UI:N/S:C/C:H/I:H/A:H",
          "baseScore": 9.3,
          "baseSeverity": "CRITICAL",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 6.0
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/34af2c3e31f91a739dc175459fdbd99ed952b457",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c624731ca6fe59ad8909ce4108301aa7560a91d6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ce447651a52ec077694172af10c4fffb11f56c43",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}