Troj/Bancban-GU is a password stealing Trojan targeted at customers of Brazilian banks.
Troj/Bancban-GU attempts to log keypresses entered into certain websites and online banking applications. The Trojan may display fake user interfaces in order to persuade the user to enter confidential details. Stolen information is sent by email to a remote user.
Troj/Bancban-GU copies itself to the Windows system folder and creates the following registry entry:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
dark
<System>\csrs.scr