An OS command injection vulnerability exists in WebTester version 5.x via the install2.php installation script. The parameters cpusername, cppassword, and cpdomain are passed directly to shell commands without sanitization. A remote unauthenticated attacker can exploit this flaw by sending a crafted HTTP POST request, resulting in arbitrary command execution on the underlying system with web server privileges.
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.