firefox.exe is a Trojan W32.Rbot-ATP. firefox.exe opens a back door on IRC channels. firefox.exe spreads via open network shares. Related files: %System%\firefox.exe More info: http://www.sophos.com/virusinfo/analyses... Removal: Kill firefox.exe process and remove firefox.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.