{
  "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-2026-64422",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64422",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-25T08:51:00.671Z",
    "updatedAt": "2026-10-19T20:38:28.132Z",
    "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": "net: ipv4: bound TCP reordering sysctl writes and MTU probe sizes",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv4: bound TCP reordering sysctl writes and MTU probe sizes\n\nReject invalid `net.ipv4.tcp_reordering` values before they reach TCP\nsocket state. The sysctl is stored as an `int` but copied into the\n`u32` `tp->reordering` field for new sockets, so negative writes wrap\nto large values.\n\nWith `tcp_mtu_probing=2`, the wrapped value can overflow the\n`tcp_mtu_probe()` size calculation and drive the MTU probing path into\nan out-of-bounds read. Route `tcp_reordering` writes through\n`proc_dointvec_minmax()` and require it to be at least 1. Also require\n`tcp_max_reordering` to be at least 1 so the configured maximum cannot\nbecome negative either.\n\nWhen registering the table for a non-init network namespace, relocate\n`extra2` pointers that refer into `init_net.ipv4` so the\n`tcp_reordering` upper bound follows that namespace's\n`tcp_max_reordering`.\n\nHarden `tcp_mtu_probe()` itself by computing `size_needed` as `u64`.\nThis keeps the send queue and window checks from being bypassed through\nsigned integer overflow.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "f0d88a4cd03affff6c08adf6c63964e235aede43"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "27ddf4486c7dbf5bdd393fa8bef6b67179796d98"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "782708ca1ea1f68b8cbb5ea3a7f5f18d0000efae"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e81f805824a8109504fce090641b17d135b48cd1"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "99206ce2244f8a3ed64298d0667c9055845a5dc7"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bbae351c0f32f7c200249e4aa6561b2b419dcf69"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a094ac95d3b69adfa1676eb9c8eae6835d4f1671"
            },
            {
              "version": "91cc17c0e5e5ada156a8d5787a2509d263ea6bbf",
              "status": "affected",
              "versionType": "git",
              "lessThan": "efb8763d7bbb40cff4cc55a6b62c3095a038149c"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "2.6.24",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "2.6.24"
            },
            {
              "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": "*"
            }
          ]
        }
      ]
    }
  }
}