1. Name:Neha Madgaonkar Roll no:411129

2.  What are intruders?  Types  Behavior  Techniques

3.  Intruder is a person who attempts to gain unauthorised control of the system and tries to destroy or damage data on the system.  One of the most common threat to security.  Often called as a hacker or cracker.  They are the ones that attempt to break security.

4. 1) masquerader  An individual who is not authorized to use the computer and who penetrates a system’s access controls to exploit a legitimate user’s account.  They are likely to be an outsider.

5. 2) Misfeasor  A legitimate user who accesses data,programs or resources for which such access is not authorized,or who is authorized for such access but misuses his or her privileges.  They are generally insider.

6. 3) Clandestine user  An individual who seizes supervisory control of the system and uses this control to evade auditing and suppress audit collection.  They can be either an outsider or insider.

7. 1) Hackers  They are the ones who hack into computers do so for thrill of it or for status.  Attackers often look for targets of opportunity and then share the information with others.  Intrusion detection system (IDS) and intrusion prevention system(IPS) can counter it.

8. 2) Criminal enterprise  Organised group of hackers.  Loosely affiliated,meet in underground forums to trade tips,data and coordinate attacks.  Common target is credit card files at e commerce site.  IDS and IPS are less effective.  Make few or no mistakes.

9. 3) Internal threat  Most difficult to detect and prevent.  It can be motivated by revenge or feeling of entitlement.  IDS and IPS may be useful to some extent.  Access the network during off hours.

10.  Most initial attacks use system that allow a user to execute code that opens a back door into the system. eg:buffer overflows.  Intruders attempt to acquire information that should have been protected.  With knowledge of some other user’s password,an intruder can log into a system and exercise all the privileges accorded to the legitimate user.

11. Any questions?

12.  Write short notes on intruders?  What are the types of intruders?  Reference  William stallings:page no-643,644,645  INTERNET:slide share