{"id":"CVE-2021-4473","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-4473","generatedAt":"2026-10-27T17:40:20.286Z","title":"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…","description":"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).","published":"2026-04-07T13:16:45.000Z","lastModified":"2026-06-17T04:19:50.000Z","status":"Analyzed","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":9.3,"severity":"CRITICAL","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-78"],"affected":["topsecgroup/tianxin internet behavior management system"],"epss":{"score":0.06165,"percentile":0.93431,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (6.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://avd.aliyun.com/detail?id=AVD-2021-890232","tags":["Third Party Advisory"],"source":"disclosure@vulncheck.com"},{"url":"https://cn-sec.com/archives/4631959.html","tags":["Exploit","Third Party Advisory"],"source":"disclosure@vulncheck.com"},{"url":"https://www.cnvd.org.cn/flaw/show/CNVD-2021-41972","tags":["Third Party Advisory"],"source":"disclosure@vulncheck.com"},{"url":"https://www.cnvd.org.cn/patchInfo/show/280166","tags":["Patch"],"source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/tianxin-internet-behavior-management-system-command-injection-via-toquery-php","tags":["Third Party Advisory","VDB Entry"],"source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-4473","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}