{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-89915",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-89915",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-16T10:32:11.309Z",
    "updatedAt": "2026-10-19T08:54:48.826Z",
    "importedAt": "2026-10-24T01:58:35.090Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "KVM: arm64: Remove VM-wide VNCR mapping counter",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Remove VM-wide VNCR mapping counter\n\nThe global VNCR mapping counter is used to decide whether an L1\nprovided VNCR page is mapped in L0 on any CPU at the point of\ndealing with a TLB invalidation. It is incremented when a mapping\nis made in the fixmap, and decremented when unmapped.\n\nAs it turns out, this tracking has several flaws:\n\n- we are trying to invalidate TLBs, and the mapping is only an\n  opportunistic consequence of the TLB. Checking this counter to\n  decide whether a TLB needs to be invalidated may result in missed\n  invalidations.\n\n- an L1 vcpu invalidating its own TLB (a very likely case) will not\n  succeed in invalidating the VNCR pseudo TLB because that page is\n  not mapped in L0 at this stage.\n\nGiven that this tracking fails at delivering the minimum guarantees\nthat are required and is only a performance optimisation, remove it\ncompletely.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5453b85c7ebb605febac3df42021f9471663f051"
            },
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "status": "affected",
              "versionType": "git",
              "lessThan": "87c2bbf189829dce4aaada8f82e3d54ccc037976"
            },
            {
              "version": "4ffa72ad8f37e73bbb6c0baa88557bcb4fd39929",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c55bc773b6e814406658fae7dc5c15f639ed816e"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.16",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.16"
            },
            {
              "version": "6.18.52",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.2.5",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "version": "7.3",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}