CVE-2021-47735 CMSimple 5.4 Authenticated Remote Code Execution via Template Editing
Authenticated attackers can inject malicious PHP code via template editing to achieve remote code execution on CMSimple installations.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-47735?
CVE-2021-47735 is a high-severity code injection vulnerability in Cmsimple, published on 23 Dec 2025. An attacker needs administrator access to exploit it, with no action from the victim.
Official 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.
Weakness: CWE-94
Which versions are affected by CVE-2021-47735?
It affects 1 product.
Products include Cmsimple Cmsimple.
How do I fix CVE-2021-47735?
No fix has been published for CVE-2021-47735 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2021-47735 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47735 exists.
Other vulnerabilities in Cmsimple
Sources
Also known as GHSA-9q7q-6c8f-q8gh.