Electronic Mail & Online SafetyHenry Van Styn, IntelliTree Solutions

http://www.intellitree.com vanstyn@intellitree.com

513-333-0282

September 17th, 2008

Agenda

• How E-Mail works– Dispel misconceptions– General understanding

• Weaknesses in E-Mail– Spam, Viruses– Overcoming weaknesses

• Online Safety– How infections/compromises occur, and why– Prevention– Correction

• Q and A

E-Mail

• Oldest Internet application

• System to relay messages

• SMTP – Simple Mail Transfer Protocol

• Modeled after postal mail

– No sender validation

E-Mail (cont.)

• Sending separate from receiving

• Protocols for receiving

– POP3

– IMAP

– Webmail

– Custom systems

E-Mail (cont.)

Sender Recipient

SMTP Server

Zip codes

E-Mail (cont.)

SMTP Server

DNS

Mail Server for xyz.com

Sender Recipient

Check mail

E-Mail (cont.)

SMTP Server

DNS

Relay Server for xyz.com

Sender Recipient

Check mail

SMTP Server

Mail Server for xyz.com

Spam

• As much as 90% of all mail is Spam• 100 billion spam messages per day

– 14 messages for every person on the planet

• Increasing– 300% increase since 2005

• Anti-Spam systems a necessity

Spam Wars

• Blacklists• Open relays closed

– Workaround: SMTP Auth

• Anti-Spam rulesets• Heuristics and Bayesian learning• Attrition

Paradigm shift - 2003

• Take over PCs - Malware• “Zombie” systems• Botnets• Unprecedented volume

Continuing Spam Wars

• URI Blacklists• OCR scanning• Real time shared anti-spam data• False positives

– Local whitelists

• Collateral damage• Keeping mail servers in “good standing”

Pandemic Spam

Cost of Spam

• Our Anti-Spam systems are 99% effective

• Server load and bandwidth usage continue to increase

• Cost US tens of billions per year

• Estimated world wide cost 2003: $20.5B*

• Estimated world wide cost 2007: $198B*

* The Radicati Group

Online Safety

• Virus authors not just vandals any longer

– Out for profit

• Take over systems - botnets

– For spamming

– For advertising

– For capturing information

– For attacking other systems

“Malware”

• Viruses

• Trojans

• Worms

• Spyware

• Adware

2 ways to become infected

• The computer gets “tricked”

• The user gets “tricked”

Exploits and patches

• Keep computer updated

• Latest security patches

• Windows updates – automatic updates

• Other updates

• Manual updates

Social Engineering

• Users pose a greater risk than un-patched software

• Don’t get tricked:

– Executing malware

– E-Mail attachments

– Web Links

– Fake error messages

Staying safe

• Common sense

• Phishing scams

• Don’t run as Administrator

• What about Anti-Virus software?

Cleaning malware

• Much easier to not get infected

• Tools:

– Spybot S&D

– Malewarebytes

– Trendmicro Housecall

• Reinstall Windows

Questions?