Transcript Computer Security

Security
WeeSan Lee [email protected]
Roadmap
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Security Risks
Preventions
References
Security Risks
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Computer Virus
Worm
Trojan Horse
Adware
Spyware
Browser Hijacker
Web Bug
Email Hoaxes & Chain Letters
Phishing
Security Risks - Computer Virus
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A small computer program that infects your
computer without permission or knowledge of
the user
Infects others via a host media
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Floppy disk
Email
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http://www.healthinitiative.org/IMAGES/virus_big.jpg
Security Risks - Worm
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A self-replicating program, spreads across
the Internet
May contain viruses
1st worm was created by Robert T. Morris, a
graduate student at Cornell U. in 1988
Computer Emergency Response Team
(CERT) was created as a result
http://tbn0.google.com/images?q=tbn:FuQHZgw5DccTfM:http://co.marion.or.us/NR/rdonlyres/481BF728-146C-49E6-8C61-3D79ADD691F2/5465/worm.JPG
Security Risks - Trojan Horse
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A program that
disguises itself to be
something useful or
harmless
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Eg. screensaver
In fact, a backdoor
program which allows
unauthorized access
remotely
http://en.wikipedia.org/wiki/Image:Trojan_horse_%C3%87anakkale.jpg
Security Risks - Adware
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An advertising-supported software
Security Risks - Spyware
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Adware + collecting user’s information
without the user’s consent
Security Risks - Browser Hijacker
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A program that changes the settings on the
web browser
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Change the homepage to other website
Security Risks - Web Bug
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Originally, use 1x1 image embedded in web
pages or HTML emails to keep track of users
AKA web beacon, tracking bug, …
To avoid that:
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Turn off image loading on email clients
Use text-based email such as pine 
http://www.prospexis.net/images/beatle2.gif
Security Risks - Hoaxes and Chain Letters
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Hoaxes are fake warnings, instructing you to
delete files, playing on your sympathy, etc
Chain letters implore you to pass the
message to as many people as possible
For examples
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“This is not a hoax.”
“Forward this email to 10 people you know for
good luck …”
“VIRUS! DELETE NTFS.SYS”
Security Risks - Phishing
Security Risks - Phishing
Preventions
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Use anti-virus/firewall software
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For examples
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AVG (http://free.grisoft.com/)
Nod32 (http://www.eset.com/)
Norton Antivirus (http://www.symantec.com/)
Schedule auto-update
Preventions (cont)
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Backup
 Use 2 HDs
 Burn CDs/DVDs and give them to your
mom
 Use online backup services
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http://www.carbonite.com/
Be educated
Don’t “fool” around
References
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Internet Effectively
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Ch 1
Ch 4
Wikipedia
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http://www.wikipedia.com/