{
  "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-2026-63867",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-63867",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-19T14:18:37.234Z",
    "updatedAt": "2026-10-19T20:17:53.288Z",
    "importedAt": "2026-10-24T01:58:20.586Z",
    "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": "mptcp: close TOCTOU race while computing rcv_wnd",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: close TOCTOU race while computing rcv_wnd\n\nThe MPTCP output path access locklessly the MPTCP-level ack_seq\nin multiple times, using possibly different values for the data_ack\nin the DSS option and to compute the announced rcv wnd for the same\npacket.\n\nRefactor the cote to avoid inconsistencies which may confuse the\npeer. Also ensure that the MPTCP level rcv wnd is updated only when\nthe egress packet actually contains a DSS ack.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "301a33fd590c408a05c5df800e0cc1e6a8a2f8f8"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "68364963e5baf03f16b4420292291f75c8f66497"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "907ac6b1658e0277f979fcdfae2a753b495c1510"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c4f4cf60797974873dbc8e100144682a6f2f861f"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3b8cbba7c0ed31189c89f90be247b8973ffa79ef"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8f4f0a157e8436a05bf8c3670b24dbc258911c43"
            },
            {
              "version": "fa3fe2b150316b294f2c662653501273ff25bba8",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8ab24fdebc369c0dfb90f82c1650b1e66662bb45"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.11",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.11"
            },
            {
              "version": "5.15.210",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.176",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.143",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.94",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.36",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.0.13",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "version": "7.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}