{
  "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-2023-53020",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-53020",
    "idYear": 2023,
    "status": "PUBLISHED",
    "publishedAt": "2025-03-27T16:43:47.151Z",
    "updatedAt": "2026-05-11T19:37:03.301Z",
    "importedAt": "2026-10-24T01:57:03.413Z",
    "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": "l2tp: close all race conditions in l2tp_tunnel_register()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nl2tp: close all race conditions in l2tp_tunnel_register()\n\nThe code in l2tp_tunnel_register() is racy in several ways:\n\n1. It modifies the tunnel socket _after_ publishing it.\n\n2. It calls setup_udp_tunnel_sock() on an existing socket without\n   locking.\n\n3. It changes sock lock class on fly, which triggers many syzbot\n   reports.\n\nThis patch amends all of them by moving socket initialization code\nbefore publishing and under sock lock. As suggested by Jakub, the\nl2tp lockdep class is not necessary as we can just switch to\nbh_lock_sock_nested().",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "37159ef2c1ae1e696b24b260b241209a19f92c60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2d77e5c0ad79004b5ef901895437e9cce6dfcc7e"
            },
            {
              "version": "37159ef2c1ae1e696b24b260b241209a19f92c60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "77e8ed776cdb1a24b2aab8fe7c6f1f154235e1ce"
            },
            {
              "version": "37159ef2c1ae1e696b24b260b241209a19f92c60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "cef0845b6dcfa2f6c2c832e7f9622551456c741d"
            },
            {
              "version": "37159ef2c1ae1e696b24b260b241209a19f92c60",
              "status": "affected",
              "versionType": "git",
              "lessThan": "0b2c59720e65885a394a017d0cf9cab118914682"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.6",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.6"
            },
            {
              "version": "5.10.166",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.91",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.9",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.2",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}