The 'itsoknoproblembro' tool was designed and implemented as a general purpose PHP script injected into a victim’s machine allowing the attacker to upload and execute arbitrary Perl scripts on the target’s machine.
The 'itsoknoproblembro' script injects an encrypted payload, in order to bypass IPS and Malware gateways into the website main file index.php, allowing the attacker to upload new Perl scripts at any time.
Initial server infection is usually done by using the well-known Remote File Inclusion (RFI) technique. By uploading Perl scripts that run different DOS flood vectors, the server might act as a Bot in a DDOS Botnet army.
Although originally designed for general purpose, some variants of this tool found in the wild were customized to act as a proprietary DDOS tool, implementing the flood vector logics inside without the need to upload additional scripts.