TROJANS

What is trojan?

• An unauthorized program contained within a legitimate program. This unauthorized program performs ffunctins unkonown by the user. 

• A legitimate program that has been altered by the placement of unauthorized code within it; this code performs functions known by the user

working of trojans

• Attacker gets access to the trojaned syastema as the system goes online.
• Byway of the access provided by the trojan attacker can stage attacks of different types.

various trojan genre

• Remote Access Trojans(RAT)
• Password Sending Trojans
• Keyloggers
• Destructive
• Denial of Services(Dos) Attack Trojans
• FTP Trojans

modes of transmissions:

Attachments, Physical access, Browser and e-mail software bugs, NetBIOS(file sharing), Fake Programs, Untrusted sites and Freeware Softwares.

Symptoms:

• System is slow
• Task Manager Disabled
• unwanted Processes
• unwanted Files or Folders on the disk

preventions:

• Donot download software from any site which is not trusted.
• Donot click on any file or folder that you are not sure what is it.
• Donot click on any unknown link.

• There are many Trojan removing software available( I dont know that they work or not, i have tried one but it didn't worked)

remember prevention is better than cure....
keep reading...