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Trojan And Backdoors – A simple Introduction and Functioning

A Trojan horse is an unauthorized program contained within a legitimate program. This unauthorized program performs functions unknown (and probably unwanted) by the user.
  • It is a legitimate program that has been altered by the placement of unauthorized
  •  code within it; this code performs functions unknown (and probably unwanted) by the user.
  • Any program that appears to perform a desirable and necessary function but that (because of unauthorized code within it that is unknown to the user) performs functions unknown (and definitely unwanted) by the user.

Working of Trojans

  • Attacker gets access to the trojaned system as the system goes online
  • By way of the access provided by the trojan attacker can stage attacks of different types.
Various Trojan Types
  • Remote Access Trojans
  • Password Sending Trojans
  • Keyloggers
  • Destructive
  • Denial Of Service (DoS) Attack Trojans
  • Proxy/Wingate Trojans
  • FTP Trojans
  • Software Detection Killers
Modes of Transmission
  • Attachments
  • Physical Access
  • Browser And E-mail Software Bugs
  • NetBIOS (File Sharing)
  • Fake Programs
  • Un-trusted Sites And Freeware Software
Backdoor Countermeasures
  • Most commercial ant-virus products can automatically scan and detect backdoor programs before they can cause damage (Eg. before accessing a floppy, running exe or downloading mail)
  • An inexpensive tool called Cleaner TROJAN REMOVER can identify and eradicate all types of backdoor programs and trojans.
  • Educate your users not to install applications downloaded from the internet and e-mail attachments.


About Lokesh Singh

Hello Friends, i am Lokesh Singh, certified Ethical hacker ( CEH, SSA, CSIF , CISSP). Have 8+ years of extensive experience in Ethical Hacking, Cyber Security and Penetration Testing domain.



    thek hei kuch had tak

  2. Nice““““““

  3. good but nots so much help full for understand its should me more easier and simple with more example detail;s or links

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