Int. J. Open Problems Compt. Math., Vol. 1, No. 2, September 2008 Computer Virus Strategies and Detection Methods Essam Al Daoud 1 , Iqbal H. Jebril 2 and Belal Zaqaibeh 3 1 Department of Computer Science, Zarqa Private University, Jordan e-mail: essamdz@zpu.edu.jo 2 Department of Mathematics, King Faisal University, Saudi Arabia 3 Department of Computer Science, Jadara University, Jordan Abstract The typical antivirus approach consists of waiting for a number of computers to be infected, detecting the virus, designing a solution, and delivering and deploying the solution, in such situation, it is very difficult to prevent every machine from being compromised by virus. This paper shows that to develop new reliable antivirus software some problems must be solved such as: a new method to detect all metamorphic virus copies, new reliable monitoring techniques to discover the new viruses or attaching a digital signature and a certificate to each new software. Keywords: Antivirus, Digital Signature, Dynamic Detection, Metamorphic Virus and Static Detection. 1 Introduction In late 1992, the number of computer viruses was estimated from 1,000 to 2,300 viruses. In 2002 there were 60,000 known viruses, Trojans, worms, and variations. Today there are well over 100,000 known computer viruses [1]. Studies and researches show that a computer connected to the Internet may experience an attack every 39 seconds [2]. New vulnerabilities in the system are discovered every few days. These vulnerabilities are fixed by the software vendors who provide patches and updates for the system. However, during this process the vulnerabilities exploit by hackers, where malicious programs are installed on user machines to steal secret data for financial gains. The compromised machines can also be made a part of a huge botnet that can be used to launch Denial of Service attacks on servers, or be used in an attempt to intrude the computers of government agencies [3].