{
  "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-2026-64514",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64514",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-25T08:52:05.878Z",
    "updatedAt": "2026-08-17T04:57:05.592Z",
    "importedAt": "2026-10-24T01:58:25.636Z",
    "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": "userfaultfd: gate must_wait writability check on pte_present()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: gate must_wait writability check on pte_present()\n\nuserfaultfd_must_wait() and userfaultfd_huge_must_wait() read the PTE\nwithout taking the page table lock and then apply pte_write() /\nhuge_pte_write() to it.  Those accessors decode bits from the present\nencoding only; on a swap or migration entry they read the offset bits that\nhappen to share the same position and return an undefined result.\n\nThe intent of the check is \"is this fault still WP-blocked?\".  A\nnon-marker swap entry means the page is in transit -- the userfault\ncontext the original fault delivered against is no longer the same, and\nthe swap-in or migration completion path will re-deliver a fresh fault if\nuserspace still needs to handle it.  Worst case under the current code the\ngarbage write bit says \"wait\", and the thread stays asleep until a\nUFFDIO_WAKE that may never arrive.\n\nGate the writability check on pte_present() so the lockless re-check only\ninspects present-PTE bits when the entry is actually present.  The\nnon-present, non-marker case returns \"don't wait\" and lets the fault path\nretry.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a5700a4c1c9099ac2ac73fe8a09cf059972e0d2f"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d4026417e8184d13850a0bad4d96ceb6ed9f7152"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "29e6f952c5fb7dc1d6b90fe5b7f36063d44ddae0"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5f4dbdb0a87596214076b20b94f2b71b522170b3"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a6e9a4939e359599701b1da351e84f72e021443a"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "60d696a037eeeedfb57756dfe7ec08a1587c8631"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "710183888174639a15fcec16cd1af766b8480bb7"
            },
            {
              "version": "369cd2121be440543280b91056de187f625d0dbb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8e80af52db652fbc41320eee45a4f73bc029faf2"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.11",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.11"
            },
            {
              "version": "5.10.261",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.212",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.178",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.145",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.96",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.39",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.1.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "version": "7.2",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}