Mal/78Crack-A is a family of downloader Trojans for the Windows platform.
Mal/78Crack-A contains functionality to download and run new executables without notification that it is doing so.
When first run Mal/78Crack-A copies itself to <Windows>\smss.exe and creates the following registry entry to run itself on startup:
HKCU\Software\Microsoft\Windows\CurrentVersion\Run
Kernel Safe Mode
<Windows>\smss.exe
Mal/78Crack-A may change the start page for Microsoft Internet Explorer by setting the following registry value:
HKCU\Software\Microsoft\Internet Explorer\Main\Start Page
Mal/78Crack-A may also launch Microsoft Internet Explorer to display popups.