This Metasploit module exploits a vulnerability found in Narcissus image configuration function. This is due to the backend.php file not handling the $release parameter properly, and then passes it on to the configure_image() function. In this function, the $release parameter can be used to inject system commands for passthru (a PHP function that's meant to be used to run a bash script by the vulnerable application), which allows remote code execution under the context of the web server.
e4e301239f9dd9233d1f53f7eeec494854791ab17cbfc496d7ff9fc4c9b4e501