{"cve":"CVE-2021-4473","nvd":{"published":"2026-04-07T13:16:44.540","modified":"2026-06-17T04:19:50.143","status":"Analyzed","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).","cvss_v4":{"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","score":9.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-78"],"references":["https://avd.aliyun.com/detail?id=AVD-2021-890232","https://cn-sec.com/archives/4631959.html","https://www.cnvd.org.cn/flaw/show/CNVD-2021-41972","https://www.cnvd.org.cn/patchInfo/show/280166","https://www.vulncheck.com/advisories/tianxin-internet-behavior-management-system-command-injection-via-toquery-php"],"products":["topsecgroup:tianxin_internet_behavior_management_system"],"source":"nvd","synced_at":"2026-10-19T22:28:59.047572785+00:00"},"epss":{"cve":"CVE-2021-4473","score":0.06165,"percentile":0.93481,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}