CMSimple is prone to multiple security vulnerabilities including:
1. Multiple arbitrary PHP code-execution vulnerabilities
2. A weak authentication security-bypass vulnerability
3. Multiple security vulnerabilities
An attacker can exploit these issues to bypass certain security restrictions, perform unauthorized actions and execute arbitrary script code in the context of the affected application. This may aid in further attacks.
Any user can login just with simple password "test" which is the default cms password & there own vendor site is vulnerable with weak authentication
just login without user name & also with default password "test" here "http://cmsimple.org/2author/?Welcome_to_CMSimple&login"