{
  "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-2021-47559",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47559",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-24T15:12:48.675Z",
    "updatedAt": "2026-08-05T08:48:24.200Z",
    "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": "net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()\n\nCoverity reports a possible NULL dereferencing problem:\n\nin smc_vlan_by_tcpsk():\n6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times).\n7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next.\n1623                ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);\nCID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS)\n8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev.\n1624                if (is_vlan_dev(ndev)) {\n\nRemove the manual implementation and use netdev_walk_all_lower_dev() to\niterate over the lower devices. While on it remove an obsolete function\nparameter comment.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "cb9d43f6775457cac75544bc4197f26ac2b6f294",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff"
            },
            {
              "version": "cb9d43f6775457cac75544bc4197f26ac2b6f294",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bb851d0fb02547d03cd40106b5f2391c4fed6ed1"
            },
            {
              "version": "cb9d43f6775457cac75544bc4197f26ac2b6f294",
              "status": "affected",
              "versionType": "git",
              "lessThan": "587acad41f1bc48e16f42bb2aca63bf323380be8"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.18",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.18"
            },
            {
              "version": "5.10.83",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.16",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}