{
  "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-2021-4473",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-4473",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2026-04-07T12:50:58.200Z",
    "updatedAt": "2026-05-14T02:06:51.986Z",
    "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": "Tianxin Internet Behavior Management System Command Injection via toQuery.php",
      "summary": "Tianxin Internet Behavior Management System contains a command injection vulnerability in the Reporter component endpoint that allows unauthenticated attackers to execute arbitrary commands by supplying a crafted objClass parameter containing shell metacharacters and output redirection. Attackers can exploit this vulnerability to write malicious PHP files into the web root and achieve remote code execution with the privileges of the web server process. This vulnerability has been fixed in version NACFirmware_4.0.0.7_20210716.180815_topsec_0_basic.bin. Exploitation evidence was first observed by the Shadowserver Foundation on 2024-06-01 (UTC).",
      "affected": [
        {
          "vendor": "Beijing Topsec Network Security Technology Co., Ltd.",
          "product": "Tianxin Internet Behavior Management System",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "4.0.0.7_20210716.180815"
            }
          ]
        }
      ]
    }
  }
}