{
  "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-2026-31504",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-31504",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-04-22T13:54:23.862Z",
    "updatedAt": "2026-10-19T18:45:53.946Z",
    "importedAt": "2026-10-24T01:58:02.025Z",
    "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: fix fanout UAF in packet_release() via NETDEV_UP race",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: fix fanout UAF in packet_release() via NETDEV_UP race\n\n`packet_release()` has a race window where `NETDEV_UP` can re-register a\nsocket into a fanout group's `arr[]` array. The re-registration is not\ncleaned up by `fanout_release()`, leaving a dangling pointer in the fanout\narray.\n`packet_release()` does NOT zero `po->num` in its `bind_lock` section.\nAfter releasing `bind_lock`, `po->num` is still non-zero and `po->ifindex`\nstill matches the bound device. A concurrent `packet_notifier(NETDEV_UP)`\nthat already found the socket in `sklist` can re-register the hook.\nFor fanout sockets, this re-registration calls `__fanout_link(sk, po)`\nwhich adds the socket back into `f->arr[]` and increments `f->num_members`,\nbut does NOT increment `f->sk_ref`.\n\nThe fix sets `po->num` to zero in `packet_release` while `bind_lock` is\nheld to prevent NETDEV_UP from linking, preventing the race window.\n\nThis bug was found following an additional audit with Claude Code based\non CVE-2025-38617.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ee642b1962caa9aa231c01abbd58bc453ae6b66e"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "42cfd7898eeed290c9fb73f732af1f7d6b0a703e"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "1b4c03f8892d955385c202009af7485364731bb9"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "654386baef228c2992dbf604c819e4c7c35fc71b"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "75fe6db23705a1d55160081f7b37db9665b1880b"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d0c7cdc15fdf8c4f91aca1928e52295d175b6ec6"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ceccbfc6de720ad633519a226715989cfb065af1"
            },
            {
              "version": "ce06b03e60fc19c680d1bf873e779bf11c2fc518",
              "status": "affected",
              "versionType": "git",
              "lessThan": "42156f93d123436f2a27c468f18c966b7e5db796"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.1",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.1"
            },
            {
              "version": "5.10.253",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.203",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.168",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.131",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.80",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.21",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19.11",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "version": "7.0",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}