Malware can take many forms such as viruses, worms, trojan horses, adware, and spyware. Viruses and worms are programs that can copy themselves and spread from computer to computer, sometimes causing harm. Adware displays advertisements, and spyware tracks personal information without consent. Phishing scams try to steal personal details through fraudulent emails or websites. Users should use antivirus software, avoid suspicious emails/attachments, and practice safe password habits to protect against malware threats.

1. Malware Fall 2006

2. Overview Malware Specific problems Computer virus, worms, trojan horses Adware, spyware Web bugs Cookies Phishing Email spoofing Solutions/Precautions

3. What’s Malware? Mal icious soft ware Software with malicious intent Different from software with bugs

4. Viruses Programs that attach themselves to another program to gain access to your machine May do nothing on your machine or may destroy all your files Seek to use your machine as a launching point to infect other machines Expand exponentially through recursion

5. Worms Like a virus but they are self-contained programs (they don’t need a host) Copy themselves from machine-to-machine Scan for other vulnerable machines

6. Adware Some programs are “free” but they support their costs by sending ads to your machine i.e. Kazaa

7. Spyware You download a music player The music player includes an additional program that is installed and runs continuously This program records the websites you visit and sends them to a database

8. How Bad is The Threat? (Bad!) 2006 Internet Security Emerging Threat List (2/15/06) (http://www.safetyonline.org) Hackers use Instant Messaging to spread viruses and worms Phishing fraud becomes more prevalent and sophisticated Viruses attack cell phones and PDAs Hackers target online brokerage accounts Internet crimes go unreported

9. What You Can (and Should) Do Install and run antivirus software Update virus definitions weekly UVA: free Norton Anti-virus Keep your computer’s operating system and programs updated Example: MS Windows, run Windows Update, weekly Run anti-spyware software Run regular sweeps/scans UVA: free SpySweeper

10. E-mail spoofing You receive e-mail appearing to be from one source…. But it's actually from another source Sender’s goal? To trick you into: Sending secure info (password, account number) Running an attachment Clicking on a link that runs a program

11. What enables spoofing? Life was simpler once upon a time… Expensive and difficult to put a mail-server on the net (and have administrator privileges on it) Managed by responsible admins: business, government, universities Open standards Today: Easy, cheap, well-understood by everyone

12. The Email

13. Where The Link Takes Me

14. The Real Bank’s Page

15. They Want Info!

16. Phishing A attempt to gain personal information for purposes of identity theft, etc. Faked e-mail messages appear to come from legitimate, official source Fool you into divulging personal data such as account numbers passwords credit card numbers Social Security numbers No company will ever ask you for such info by e-mail. If in doubt, call them or contact them directly (not by replying)

17. Examples Bank of America scam

18. E-mail Lessons Do not open attachments unless you know what they are Antivirus software checks attachments as you open them! Suspect spoofing Look for anything odd in the message Double-check with sender Phishing: don’t get caught Be suspicious. Look for your name, account number, etc. in an e-mail Don’t click on links, go directly to the site.

19. Virus through a Link in an Email Link seems to be to CS dept. (www.cs.virginia.edu) That’s the text of the link It links to someplace else An attachment that is disguised so it doesn’t appear The small box is the only clue

20. What Is a Cookie? A small piece of information stored by your web-browser on your PC when you visit a site What’s stored: A URL related to the site you visited A name/value pair (the information content) (Optional) An expiration date Why is it a “cookie”? An old CS term for a chunk of data used obscurely

21. Cookies: Web-servers Store Some Info on your PC When sending back a page, server also sends a cookie Your browser stores it on your PC Later, visit same site You request a page and your browser has a cookie matching that URL on your PC Browser sends URL and cookie to web-server Web-server processes cookie May return updated cookies with page

22. Cookies Can Be Beneficial Shopping Carts Server creates a cart, stored on server You visit other pages, but a cookie lets the server know you’re the person who created that cart Other personalization “Welcome back, Jane User!” “Items you viewed recently are…” Recognizing legitimate users for a site Register and log-in, but then a cookie means you don’t have to log-in every time

23. What’s a Web Bug? Graphic image on a Web page or in an Email message Links to an external site, not an image embedded in your message Designed to monitor who is reading the Web page or Email message May be invisible (size 1 pixel by 1 pixel) or not Sometimes knowns as a "clear GIFs", "1-by-1 GIFs" or "invisible GIFs“ (More info: http:// www.eff.org/Privacy/Marketing/web_bug.html )

24. How Does This Work? Web bug: on some other server Remember: when a server delivers a HTML file or an image file, it logs this A page or an email can have an image that’s stored on some external site Thus the server there logs delivery of that image (even if it’s invisible to you)

25. Examples (in HTML) <img src=&quot;http://ad.doubleclick.net/ad/pixel.quicken/NEW&quot; width=1 height=1 border=0> <img width='1' height='1' src=&quot;http://www.m0.net/m/logopen02.asp? vid=3&catid=370153037&email=SMITHS%40tiac.net&quot; alt=&quot; &quot;>

26. What Info Can Be Gathered? Again, the server where the bug lives will log: The IP address of your computer The URL of the page that the Web Bug is located on The URL of the Web Bug image The time the Web Bug was viewed The type of browser that fetched the Web Bug image Also possible: Info from any cookie that's on your machine

27. Web Bugs: What Can You Do? Not easy to identify web bugs New email clients disable image display

28. Browser Hijack An extremely nasty adware Resets homepage to a particular site Ads, porn – something you don’t want Any change you make doesn’t affect it Software running on your machine Does the usual adware/spyware stuff Also changes your browser settings Runs when system starts – changes the settings back

29. Protecting Your Computer Practice the core three protections Install Configure Regularly update Do not open unexpected emails Do not download attachments in unsolicited emails Take precautions to protect your mobile devices Reporter Internet crimes to proper authorities

30. Passwords Use strong passwords At least 8 characters with numbers and symbols Don’t use real words Don’t use the same password for every online account Vary your passwords for each site, and use a password profiler tool

31. Resources Top 8 Cyber Security Practices http:// www.staysafeonline.info/practices/index.html

32. Review Midterm next Wednesday Another review session Tuesday 11AM Short answer and multiple choice.

33. Outline Ethics: no ethics on exam Internet history: what’s the difference between the web and the Internet Packet switching HTML Be able to translate some basic HTML into output (formatting, links, images) CSS: what is the purpose

34. Outline II JavaScript: no JavaScript code Difference between dynamic and static pages Spreadsheets Why use them? Why use referencing? Produce output from sample formulas PowerPoint Terms Search Engines What do spiders do? MetaTags?

35. Outline III Digital audio What is sampling? Compression? Malware Know types and some good practices Not on midterm: Ethics, binary & hex, JavaScript code