CVE-2021-4473

CRITICAL EPSS 92.6%
Published Apr 7, 20262mo ago · Modified Jun 17, 20261w ago
9.3 CVSS 4.0
Critical
Find Similar
Published Apr 7, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago

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 Details

Base Score
9.3
Exploitability
Impact
Vector string
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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
92.6% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-78 OS Command Injection Injection

Affected Products 1

VendorProductVersionRange
topsecgrouptianxin_internet_behavior_management_system* <4.0.0.7_20210716.180815

References 5

  • avd.aliyun.com https://avd.aliyun.com/detail?id=AVD-2021-890232
    Third Party Advisory
  • cn-sec.com https://cn-sec.com/archives/4631959.html
    ExploitThird Party Advisory
  • cnvd.org.cn https://www.cnvd.org.cn/flaw/show/CNVD-2021-41972
    Third Party Advisory
  • cnvd.org.cn https://www.cnvd.org.cn/patchInfo/show/280166
    Patch
  • vulncheck.com https://www.vulncheck.com/advisories/tianxin-internet-behavior-management-system-command-injection-via-toquery-php
    Third Party AdvisoryVDB Entry

Remediation

  • cnvd.org.cn https://www.cnvd.org.cn/patchInfo/show/280166
    Patch