{
  "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-2025-40173",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-40173",
    "idYear": 2025,
    "status": "PUBLISHED",
    "publishedAt": "2025-11-12T10:53:49.571Z",
    "updatedAt": "2026-10-15T22:02:39.584Z",
    "importedAt": "2026-10-24T01:57:34.152Z",
    "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/ip6_tunnel: Prevent perpetual tunnel growth",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/ip6_tunnel: Prevent perpetual tunnel growth\n\nSimilarly to ipv4 tunnel, ipv6 version updates dev->needed_headroom, too.\nWhile ipv4 tunnel headroom adjustment growth was limited in\ncommit 5ae1e9922bbd (\"net: ip_tunnel: prevent perpetual headroom growth\"),\nipv6 tunnel yet increases the headroom without any ceiling.\n\nReflect ipv4 tunnel headroom adjustment limit on ipv6 version.\n\nCredits to Francesco Ruggeri, who was originally debugging this issue\nand wrote local Arista-specific patch and a reproducer.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "566f8d5c8a443f2dd69c5460fdec43ed1c870c65"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "11f6066af3bfb8149aa16c42c0b0c5ea5b199a94"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "402b6985e872b4cf394bbbf33b503947a326a6cb"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "10fe967efe73c610e526ff7460581610633dee9c"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "48294a67863c9cfa367abb66bbf0ef6548ae124f"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "eeb4345488672584db4f8c20a1ae13a212ce31c4"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b6eb25d870f1a8ae571fd3da2244b71df547824b"
            },
            {
              "version": "8eb30be0352d09165e94a41fef1c7b994dca0714",
              "status": "affected",
              "versionType": "git",
              "lessThan": "21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.7",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.7"
            },
            {
              "version": "5.4.301",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "version": "5.10.246",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.196",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.158",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.114",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.55",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.17.5",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.17.*"
            },
            {
              "version": "6.18",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}