Viruses Juan Arriola CS-100

HISTORY Computers viruses first appeared with the credit of John von Neumann due to his studies on the self replication of mathematical automata in the 1940’s. Then the idea of viruses infecting computers and their programs emerged in the 1970’s leading to the first recorded case of the Brain virus at the University of Delaware in late 1987.

What is a Virus? A computer virus is a piece of software designed and written to make additional copies of itself and spread, typically without user knowledge or permission. Some viruses display symptoms, and some cause damage to files in the system that have been infected. Since a virus is code that was not intentionally installed by the user, there are no "good" viruses. When a virus finds itself in a different environment than that for which it was written, a non-destructive virus can become destructive.

There are 4 main classes of viruses: 1.Boot-sector viruses 2.Program file viruses 3.Multi-partite viruses 4.Macro viruses

How Do Computers Become Infected? 1.Viruses can be hidden in programs available on floppy disks or CDs, hidden in attachments or in material downloaded from the web. 2.Once the virus is active on the computer, it can copy itself to (infect) other files or disks as they are accessed by the user.

How do they work? How do they work? Viruses work in a multitude of different ways: They can damage important operating system files After infecting your computer, they spread themselves to other computers by using your Internet connection when you’re online. They can collect important information about the users of the computers the viruses infect and send it back to the author

How do they work? They can send s (without you even opening your program) to everyone in your address book from you that contain the virus. They can also spread through other connections that your computer maintains to the Internet. They can produce annoying pop-up advertisements (even when you’re not on the Internet), they can crash websites, and pretty much anything else you can imagine.

How do I get infected? Most viruses infect computers through application files of some kind (attachment files with a.EXE or.SCR extension are the most typical). The user of the computer (you) has to physically open the application file. Most viruses come through as an attachment to an message. However, since 2003, viruses have become more advanced and can actually infect your computer through open connections to the Internet.

Why do people write them? People can write viruses to collect important information (like credit card numbers) for malicious intent, to see how many computers they can infect and, in some cases, people write viruses to crash websites (like the Blaster worm of August 2003 which was written to crash Microsoft’s website).

What are some common computer viruses? Netsky Blaster Sobig Melissa Lovletter Chernobyl Klez Nimda Lirva

Viruses Names Netsky Win32.Netsky.AB Win32.Netsky.AC Win32.Netsky.B Win32.Netsky.C Win32.Netsky.D Win32.Netsky.P Win32.Netsky.Q Win32.Netsky.S Win32.Netsky.T Win32.Netsky.W Win32.Netsky.Y Win32.Netsky.AB Win32.Netsky.AC Win32.Netsky.B Win32.Netsky.C Win32.Netsky.D Win32.Netsky.P Win32.Netsky.Q Win32.Netsky.S Win32.Netsky.T Win32.Netsky.W Win32.Netsky.Y Win32.Netsky.AB Win32.Netsky.AC Win32.Netsky.B Win32.Netsky.C Win32.Netsky.D Win32.Netsky.P Win32.Netsky.Q Win32.Netsky.S Win32.Netsky.T Win32.Netsky.W Win32.Netsky.Y Msblast: Win32.Msblast.A Win32.Msblast.A BugBear: Klez: CodeRed: Win32.IISWorm.CodeRe d.F Win32.IISWorm.CodeRe d.F Win32.IISWorm.CodeRe d.F

Safe Computing practices! Anti-Virus software Scan your computer on a regular basis Update your Anti- Virus Software on a regular basis Backup your files on a regular basis Scan & Protect Floppy Disks Scan Attachments Beware of Attachments from unknown sources Be Alert

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