CVE-2021-4473

9.8 CRITICAL
Published: April 07, 2026 Modified: April 24, 2026
View on NVD

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).

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://avd.aliyun.com/detail?id=AVD-2021-890232
Source: disclosure@vulncheck.com
Third Party Advisory
https://cn-sec.com/archives/4631959.html
Source: disclosure@vulncheck.com
Exploit Third Party Advisory
https://www.cnvd.org.cn/flaw/show/CNVD-2021-41972
Source: disclosure@vulncheck.com
Third Party Advisory
https://www.cnvd.org.cn/patchInfo/show/280166
Source: disclosure@vulncheck.com
Patch

5 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
5.4%
90th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

topsecgroup