{
  "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-2021-47507",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47507",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-24T15:01:53.401Z",
    "updatedAt": "2026-05-23T15:20:06.443Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "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": "nfsd: Fix nsfd startup race (again)",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: Fix nsfd startup race (again)\n\nCommit bd5ae9288d64 (\"nfsd: register pernet ops last, unregister first\")\nhas re-opened rpc_pipefs_event() race against nfsd_net_id registration\n(register_pernet_subsys()) which has been fixed by commit bb7ffbf29e76\n(\"nfsd: fix nsfd startup race triggering BUG_ON\").\n\nRestore the order of register_pernet_subsys() vs register_cld_notifier().\nAdd WARN_ON() to prevent a future regression.\n\nCrash info:\nUnable to handle kernel NULL pointer dereference at virtual address 0000000000000012\nCPU: 8 PID: 345 Comm: mount Not tainted 5.4.144-... #1\npc : rpc_pipefs_event+0x54/0x120 [nfsd]\nlr : rpc_pipefs_event+0x48/0x120 [nfsd]\nCall trace:\n rpc_pipefs_event+0x54/0x120 [nfsd]\n blocking_notifier_call_chain\n rpc_fill_super\n get_tree_keyed\n rpc_fs_get_tree\n vfs_get_tree\n do_mount\n ksys_mount\n __arm64_sys_mount\n el0_svc_handler\n el0_svc",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "8677e99150b0830d29cc1318b4cc559e176940bb",
              "status": "affected",
              "versionType": "git",
              "lessThan": "f5734b1714ca355703e9ea8fb61d04beff1790b9"
            },
            {
              "version": "7c7cb07d4affcf41749234fe9dc4d90cd3959e32",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c520943a00ad5015704969ad3304c956bcd49d25"
            },
            {
              "version": "bd5ae9288d6451bd346a1b4a59d4fe7e62ba29b7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8bf902fee5893cfc2f04a698abab47629699ae9a"
            },
            {
              "version": "bd5ae9288d6451bd346a1b4a59d4fe7e62ba29b7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b10252c7ae9c9d7c90552f88b544a44ee773af64"
            },
            {
              "version": "4d41f65efeec0a6da6088341203c81e49ebfcd90",
              "status": "affected",
              "versionType": "git"
            },
            {
              "version": "5.4.102",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.4.165"
            },
            {
              "version": "5.10.20",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.10.85"
            },
            {
              "version": "5.11.3",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.12"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.12",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.12"
            },
            {
              "version": "5.4.165",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "version": "5.10.85",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.8",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.16",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}