IntroductionDefinition / DescriptionA ‘Trojan’ is a type ofmalware. A Trojan may be in the form of a program or file, and its mode ofdelivery is designed by deceiving a user by posing as an application.
A Trojan’sentire identity rests on praying on a user by baiting them into clicking anapplication and consequently opening the Trojan. An important characteristicof a Trojan is that the application it they are often designed after may be a masterfullyconvincing representation of a safe and recognizable application that the useralready trusts. Methods of infectionUnlike worms orviruses, the Trojan is does not self-replicate. A Trojan infects a by copyingitself onto a compromised system. This is done severalways as Trojans rely on manual distribution under the guise of what the userexpected. These distribution methods include but are not limited to peer-to-peernetworks, website/blog postings, spim, drive by downloads, chat room links, andmost notoriously spam.
Drive by downloads areparticularly dangerous. This is a type of Trojan which some may debate thatoccurs when a user simply opens a trusted website that has been the victim ofexploitation and ergo the Trojan infects the user simply by opening the webpage.Trojans may appear in asomething you download from web or even from your school, work, or a trustedfriend. A Trojan when may appear to be an attachment or a download in the inthe forms of (but not limited to) an .
exe, .jpg file, or a .doc file. RisksWhen a Trojan is installedonto a computer, it then executes the malicious code. It should be noted that someTrojans even have been written to appear as if they are doing whatever it isthe user opened them to do, however, the Trojan is in fact triggering maliciouscode.The purposes behindwhich the authors program Trojans vary.
The vast range of a Trojan attacksinclude but are not limited to: DDOS / DOS, stealing files and data, disarming backdoors and security features, and distributing a payload malware.It should be noted thatthe potential for identity theft is particularly high if a Trojan steals yourfiles and data. PreventionThe following is a general list for user to apply inany environment to mitigate the risk of a Trojan infection. Turn off file sharing Disable AutoPlay.Turn off or remove applicationsservices or programs.Do not open or executefiles from unknown sources.Check and update antivirussoftware.
Use a firewall. Update patch levels.Disable AutoPlay.Turn off Bluetooth.Usea password policy.Removal A TrojanRemoving a Trojan from yoursystem once identified may be done in a few ways. Below I will identify a few. Oneway users may remove some Trojans from their system is by using a removal tool.
If a user happens to havean infected OS system file they would need to replace the file using theoriginal OS installation CD.Often a Trojan willperform tasks which then make modifications to the system registry which then maytake a tool on the overall health of the system. It may be necessary to editthe registry and delete sub keys and entries created by the functions of the Trojanand return any altered keys to their preexisting values.