CVE-2021-47735 HIGH

CVE-2021-47735: CMSimple 5.4 Authenticated Remote Code Execution via Template Editing

Vendor Cmsimple
Product Cmsimple
Weakness CWE-94 · Code injection
Published December 23, 2025
Last update March 5, 2026

CVSS base score

8.6/10
Attack vector Network
Attack complexity Low
Privileges required High
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

December 23, 2025 CVE published
March 5, 2026 Record updated