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Video. Following is a video of what can happen if you don’t update your security settings!. Protecting Yourself in Cyberspace. BBI 1OE. Viruses. What are viruses? Are programs that insert themselves into your computer Are activated when you run an infected program or open a file
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Video Following is a video of what can happen if you don’t update your security settings!
Viruses What are viruses? • Are programs that insert themselves into your computer • Are activated when you run an infected program or open a file • Immediately start to replicate themselves by looking for new areas to infect
Viruses Are all viruses the same? Boot-sector File Macro
Boot-Sector Viruses • Infect the boot sector of a computer’s disk or hard drive • It substitutes its code over code read by your computer when it is turned on or restarted • Forces the computer to read its code into memory and pass control to the virus code
Boot-Sector Viruses Brain Virus:a boot sector of storage media formatted with the DOS File Allocation Table • Created in Pakistan in 1986 • First known computer virus
File Viruses • Use a computer’s file system to propagate (grow and reproduce) • Work by infecting files when they are being opened, renamed, or saved • Cause messages to appear on screen
File Viruses Jerusalem Virus Dark Avenger Dir II
Macro Viruses • Programs written in macro languages (programming language) • Are designed to operate in specific software applications • Instructions attached to a document file that tell the software application to perform commands automatically • Propagate by transferring from one infected file to another • Common in programs like Microsoft Word, Excel and email applications
Macro Viruses Melissa Virus
Main Virus Infection Types • Worm – replicates itself and slithers through networks or email to infect computers • Are a malicious code that do not attach themselves to other files or programs • Trojans – a destructive program that pretends to be something else that users would want on their computer • Are also a form of malicious code (e.g. pretending to be virus protection software)
Main Virus Infection Types • Stealth – hides the modifications it has made to the files or boot records • Programs that try to read infected files may only see the original uninfected form • Polymorphic – produces slightly different copies of itself because it assumes the anti-virus software will not detect it • Armour – uses special tricks to make the tracing of its code more difficult
How Do Computers Catch a Virus? • Disks, CD-ROMs, and DVDs – leave an infected disk in the drive and restart • Internet & Email – files found on the Web can be infected and attached to emails • LANs – unless protected, virus can spread throughout the network • People – can program or save viruses on an unsuspecting computer
Protecting Against Viruses • Use anti-virus software and a firewall • Back up your files regularly • Protect your computer with a password • Lock your computer when it is not in use
Protecting Against Viruses • Firewall – software that prevents certain information from entering or leaving your computer when online • Anti-virus software scans your hard drive and other storage media to locate and destroy viruses • Scan all disks and removable storage with anti-virus software
Protecting Against Viruses • Encryption – encode information in a manner that only the person (or computer) with the key can decode it
It’s Viral! Working in groups of four: • Research the different types of anti-virus software that exist and what features they have • Research and describe 5 of the worst computer viruses of all time