CVE-2021-47735 - CVE House
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Status published High CVE-2021-47735

CMSimple 5.4 Authenticated Remote Code Execution via Template Editing

Vulnerability Description

CMSimple 5.4 contains an authenticated remote code execution vulnerability that allows logged-in attackers to inject malicious PHP code into template files. Attackers can exploit the template editing functionality by crafting a reverse shell payload and saving it through the template editing endpoint with a valid CSRF token.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • pussycat0x

References

More from Cmsimple

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CVE-2021-47734
CMSimple 5.4 Authenticated Local File Inclusion Remote Code Execution
High 8.6
CVE-2021-47733
CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding
Medium 5.1

Affected Vendor

Affected Software

Cmsimple
Vulnerable Versions:
5.4

Timeline

Official Publish: December 23rd, 2025
Last Modified: March 5th, 2026
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses (CWE)

CWE-94

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1505.003 Web Shell
Persistence
T1105 Ingress Tool Transfer
Command and Control
T1565.002 Stored Data Manipulation
Impact