The developer rewrote a large part of the code however the workflow is the same as previously and some features are copy/paste. The biggest change is the network communication with the C2 server. The malware does not use a raw socket anymore but all the communications are performed with WinInet. The malware performs connection to the C2 server by using InternetOpenA() with an hardcoded User-Agent: "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; .NET CLR 1.1.4322". Note the missing parenthesis at the end of the User-Agent. This variant has exactly the same features as the previous variant: file listing, OS version getting, process killing, drive listing, execution via ShellExecuteW(), execution via named pipe, cleaning, file removal, file downloading. Here is an example of code similarities on the execution via named pipe function. On the left a sample from Bisonal 2014 and on the right Bisonal 2011. The code is not exactly the same but the workflow and some constants are similar