Computer Viruses
Introduction zComputer virus have become today’s headline news zWith the increasing use of the Internet, it has become easier for virus to spread zVirus show us loopholes in software zMost virus are targeted at the MS Windows OS
Definition ÞVirus : A true virus is capable of self replication on a machine. It may spread between files or disks, but the defining character is that it can recreate itself on it’s own with out traveling to a new host
Overview zBackground zSymptoms zClassifying Viruses zExamples zProtection/Prevention zConclusion
Background zThere are estimated 30,000 computer viruses in existence zOver 300 new ones are created each month zFirst virus was created to show loopholes in software
Virus Languages zANSI COBOL zC/C++ zPascal zVBA zUnix Shell Scripts zJavaScript zBasically any language that works on the system that is the target
Symptoms of Virus Attack z Computer runs slower then usual z Computer no longer boots up z Screen sometimes flicker z PC speaker beeps periodically z System crashes for no reason z Files/directories sometimes disappear z Denial of Service (DoS)
Virus through the Internet zToday almost 87% of all viruses are spread through the internet (source: ZDNet) zTransmission time to a new host is relatively low, on the order of hours to days z“Latent virus”
Classifying Virus - Categories zStealth zPolymorphic zCompanion zArmored
Classifying Virus - Types zTrojan Horse zWorm zMacro
Trojan Horse zCovert zLeaks information zUsually does not reproduce
Worms zSpread over network connection zWorms replicate zFirst worm released on the Internet was called Morris worm, it was released on Nov 2, 1988.
Macro zSpecific to certain applications zComprise a high percentage of the viruses zUsually made in WordBasic and Visual Basic for Applications (VBA) zMicrosoft shipped “Concept”, the first macro virus, on a CD ROM called "Windows 95 Software Compatibility Test" in 1995
Protection/Prevention zKnowledge zProper configurations zRun only necessary programs zAnti-virus software zFirewalls zOpen from known senders
Conclusion zYou know know more about virus and how: yviruses work through your system yto make a better virus zHave seen how viruses show us a loophole in popular software zMost viruses show that they can cause great damage due to loopholes in programming
Questions? Copies of the latest lovebug virus code are available…in print