Malware and how to defend against it Tommy Wei

What is Malware? FEAR ME! Stands for malicious software It is software Usually created by computer programmers Examples of software:

Personal Vigilance Being careful and pay attention Popular way of spreading malware is by email Recognize traps Ask you to open attachments Provide passwords or classified information Try to pose as a friend Enticing emails Certain websites

Disadvantages of Personal Vigilance Human Error Business and web security isn’t perfect

Antivirus Software Packages The primary component of technological defenses for every computer Well designed antivirus software include the following characteristics: Automatically checks newly downloaded programs for malware Scans computer periodically Is regularly updated Also detect and warn against suspicious websites based on similar technical features

Signature Approach (Virus Dictionary) Examines files and searches for viruses listed in the virus dictionary Virus dictionary- a predetermined list of current viruses Is this a virus? Let me check if its here.

Disadvantages Virus dictionary has to be constantly updated Can be circumvented by encrypting parts of the virus Changes virus signature Becomes a polymorphic virus

Heuristics Approach (Suspicious behavior) Hmmm, who are you? gives your antivirus software some degree of intelligence Depends on the behavior of the program, deemed suspicious or not You look okay.

Disadvantages No, No. I approve of that! It can be inaccurate at detecting valid viruses Make mistakes called “false positives” Requires manual intervention to fix mistakes