CVE-2021-47735

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.cmsimple.org/	Product
https://www.exploit-db.com/exploits/50356	Exploit
https://www.vulncheck.com/advisories/cmsimple-authenticated-remote-code-execution-via-template-editing	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cmsimple:cmsimple:5.4:*:*:*:*:*:*:*

History

31 Dec 2025, 21:43

Type	Values Removed	Values Added
References	~~() https://www.cmsimple.org/ -~~	() https://www.cmsimple.org/ - Product
References	~~() https://www.exploit-db.com/exploits/50356 -~~	() https://www.exploit-db.com/exploits/50356 - Exploit
References	~~() https://www.vulncheck.com/advisories/cmsimple-authenticated-remote-code-execution-via-template-editing -~~	() https://www.vulncheck.com/advisories/cmsimple-authenticated-remote-code-execution-via-template-editing - Third Party Advisory
First Time		Cmsimple Cmsimple cmsimple
CPE		cpe:2.3:a:cmsimple:cmsimple:5.4:::::::*

23 Dec 2025, 20:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-23 20:15

Updated : 2025-12-31 21:43

NVD link : CVE-2021-47735

Mitre link : CVE-2021-47735

CVE.ORG link : CVE-2021-47735

JSON object : View

Products Affected

cmsimple

cmsimple

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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