{
  "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-2021-47356",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47356",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-21T14:35:59.097Z",
    "updatedAt": "2026-05-11T13:53:07.476Z",
    "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": "mISDN: fix possible use-after-free in HFC_cleanup()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmISDN: fix possible use-after-free in HFC_cleanup()\n\nThis module's remove path calls del_timer(). However, that function\ndoes not wait until the timer handler finishes. This means that the\ntimer handler may still be running after the driver's remove function\nhas finished, which would result in a use-after-free.\n\nFix by calling del_timer_sync(), which makes sure the timer handler\nhas finished, and unable to re-schedule itself.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "49331c07ef0f8fdfa42b30ba6a83a657b29d7fbe"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "54ff3202928952a100c477248e65ac6db01258a7"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "7867ddc5f3de7f289aee63233afc0df4b62834c5"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5f2818185da0fe82a932f0856633038b66faf124"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3ecd228c636ee17c14662729737fa07242a93cb0"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b7ee9ae1e0cf55a037c4a99af2acc5d78cb7802d"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "61370ff07e0acc657559a8fac02551dfeb9d3020"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ed7c3739d0a07e2ec3ccbffe7e93cea01c438cda"
            },
            {
              "version": "87c5fa1bb42624254a2013cbbc3b170d6017f5d6",
              "status": "affected",
              "versionType": "git",
              "lessThan": "009fc857c5f6fda81f2f7dd851b2d54193a8e733"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "2.6.29",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "2.6.29"
            },
            {
              "version": "4.4.276",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.4.*"
            },
            {
              "version": "4.9.276",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.9.*"
            },
            {
              "version": "4.14.240",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.14.*"
            },
            {
              "version": "4.19.198",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "4.19.*"
            },
            {
              "version": "5.4.133",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.4.*"
            },
            {
              "version": "5.10.51",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.12.18",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.12.*"
            },
            {
              "version": "5.13.3",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.13.*"
            },
            {
              "version": "5.14",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}