CVE-2021-4473

Critical

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).

SeverityCritical

CVSS9.8

Exploit probability—

ProductTopsecgroup Tianxin Internet Behavior Management System

PublishedApr 7, 2026

First seenApr 7, 2026

Weakness typeCWE-78OS command injection

How to fix

Update

topsecgroup tianxin_internet_behavior_management_system4.0.0.7_20210716.180815 or later

Patches

cnvd.org.cn/patchInfo/show/280166

Affected products

Product	Affected versions	Fixed in
topsecgroup tianxin_internet_behavior_management_system	v < 4.0.0.7_20210716.180815	4.0.0.7_20210716.180815

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