CVE-2021-4473

CRITICAL EXPLOITED

Tianxin Internet Behavior Management System Command Injection via toQuery.php

Title source: cna
STIX 2.1

Exploitation Summary

CVE-2021-4473 has been observed exploited in the wild (reported by VulnCheck KEV).

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).

References (5)

Core 5

Scores

CVSS v3 9.8
EPSS 0.0617
EPSS Percentile 92.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

VulnCheck KEV 2026-04-07
CWE
CWE-78
Status published
Products (2)
Beijing Topsec Network Security Technology Co., Ltd./Tianxin Internet Behavior Management System < 4.0.0.7_20210716.180815
topsecgroup/tianxin_internet_behavior_management_system < 4.0.0.7_20210716.180815
Published Apr 07, 2026
Tracked Since Apr 07, 2026