CVE-2021-4473

Tianxin Internet Behavior Management System Command Injection via toQuery.php

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

Beijing Topsec Network Security Technology Co., Ltd. · Tianxin Internet Behavior Management System

CVSS v4.0 VULNCHECK

9.3 CRITICALCVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1 VULNCHECK

9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

6.17% chance of exploitation in the next 30 days, 93rd percentile

Published

2026-04-07

Updated

2026-05-14

Proof-of-concept exploits (1)

• https://cn-sec.com/archives/4631959.html

Security advisories

• https://avd.aliyun.com/detail?id=AVD-2021-890232
• https://www.cnvd.org.cn/flaw/show/CNVD-2021-41972
• https://www.vulncheck.com/advisories/tianxin-internet-behavior-management-system-command-…
• https://www.cnvd.org.cn/patchInfo/show/280166

References

• CVE Record
• NVD entry