{
  "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-2026-89593",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-89593",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-11T19:44:56.557Z",
    "updatedAt": "2026-10-19T08:49:25.740Z",
    "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": "hugetlb: only adjust reservation during unmapping if mapcount is 0",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nhugetlb: only adjust reservation during unmapping if mapcount is 0\n\nSince df7a6d1f6405, __unmap_hugepage_range can adjust reservations.  In\nthe case of folio mapped in both a parent and a child, if the parent\nunmaps the range first, the reservation adjustment will result in an\nunderflow of the reserved count.  Once the child unmaps the range, the\ncount is restored.  Change __unmap_hugepage_range() to check the mapcount\nbefore adjusting the reservation.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b0b1b9ca80b795ed2223e76dd787db7067121fb9"
            },
            {
              "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a3c65af20cceb7f997847727636b4017326f845d"
            },
            {
              "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "0f001491e5a2ec69aa9d5dd6b799e5742245f9ea"
            },
            {
              "version": "df7a6d1f64056aec572162c5d35ed9ff86ece6f3",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5120b1e048d48596ffaec1a8412012a91adba73b"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.9",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.9"
            },
            {
              "version": "6.12.110",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.50",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.2.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "version": "7.3",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}