55 Plus

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55 Plus

• Feb 14 2005

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Agenda

• Computer Threats what they are and how to cope
  
• File Associations how applications are started
  why you cant always open email attachments
• Mike Lawrance Looking at emails without
  opening.
• Q A your turn to ask question and hopefully
  get answers

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Different Threats
SPAM
What do they have in common?

• MALWARE
• Virus
• Worm
• Spyware

They Are a Pain In The Neck
Computer Hacking

• Require
• 3 different utilities
• Maybe from same vendor

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Disclaimer
This topic is complex, and different individuals
may view it differently. The content has been
simplified and thus could be challenged by
computer professionals. It will however give you
a good idea of the threats and hopefully what you
can do to adequately protect yourselves. I read a
comment by an individual who suggested the only
way to truly protect oneself is to have two
computers - one connected to the internet and
other not. You would then copy the files you
wanted from one to the other. I not sure if I
even totally agree with that statement.
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Computer Hacking

• Intruders access your computer without your
  permission!
• Once the intruder is inside, they can do what
  they like!
• How might they get access?
• Home invasion example
• Unlocked door
• Open window
• Look for some point of vulnerability
• Internal set up
• Owners carelessness

• With computers
• Most times it is via the network
• holes in the software
• doors windows left open
• Set up by a virus

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Computer Hacking

• How do you protect?
• In homes
• Install locks, alarms and intercoms. We might
  even install perimeter monitoring systems.
• Fix problem areas
• Start a Block Watch
• Use unlisted telephone numbers
• For computer
• Install firewalls - software and/or hardware
• Keep Operating System updates current
  particularly with security
• Disconnect from the internet when not using
  maybe!
• Be careful with for your identity
• Close open doors if you know what they are.

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Computer Hacking
S/W firewall Blocks designated traffic in and
out H/W Firewall Blocks designated traffic in
and out Plus isolates computers behind firewall
Network users can only see my gateway (router)
address. I am hidden from their view.
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Spam

• A bit like the junk mail the postman delivers
  with one big exception
• there are virtually no constraints
• if I have to buy a stamp I might think twice
• there are no postage costs on the internet.
• How do they find you?
• Harvesting Webpages
• Harvesting Newsgroups
• Social Engineering e.g. greeting cards sites
• Guessing
• Theft a crafty website , a worm, a chain
  letter.
• Buying
• Sniffing

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Spam

• How do you control
• Be careful who gets your email
• Use Spam filters provided by internet
  providers, commercial products
• How does a spam filter work
• Look for irregularities
• Block known offenders
• Rule based filtering
• Issues
• May block legitimate
• Spammers use tricks to fool filter rules e.g.
  spelling errors
• Personally I dont think it will ever completely
  go away.

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Malware
Malware" is short for malicious software and is
typically used as a catch-all term to refer to
any software designed to cause damage to a single
computer, server, or computer network, whether
it's a virus, spyware, etc.

• Different types
• Virus
• Worm
• Trojan Horse
• Spyware

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Malware

• The difference between a virus and a worm is
  where they live and how they propagate.
• A virus attaches itself to another program or
  executable e.g. a Word document macro.
• When a user opens up an object with a virus, the
  virus it will start spreading e.g. if you
  receive a word document with a virus and open
  that document it might then infect every other
  word document you open. When you pass along any
  of the infected documents the virus will continue
  to spread as individuals open up the document.

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Malware
A worm is self contained. If you are infected
with worm, it will likely start when you start
your computer and begin spreading without any
additional actions by you. One way it might do
that is to look through you address book and send
emails to individuals in you address book and
include itself on the email. The unsuspecting
individual receiving the email, will when they
open the email, infect their computer and the
propagation continues.
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Malware

• A Trojan Horse is a way a virus or worm is spread
  by pretending to be something else.
• The are 2 stages of a virus / worm
• The infectious stage - where spreads
• The destructive stage - when it will do its
  damage
• Remember a virus/worm is a program it can do
  anything a program can do
• Erase files
• Erase files on a particular day
• Erase files after it has attempted to infect x
  others
• Etc.
• Sometimes the damage is caused by the network
  traffic generated
• Sometime the damage could be done by sending
  confidential information to whoever.

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Malware

• Spyware is similar to a virus or worm in that it
  is installed on your computer without your
  consent.
• Their purpose is the send information about you
  to someone
• About your computer use habits
• Confidential information
• Etc
• They usually do not propagate and are installed
  when you install a particular products. Sometime
  they are necessary for the program to work
• Ad Pop-Ups are also installed without your
  consent or are part of the application you are
  using. They generate those annoying advertising
  pop-up.

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Malware

• Detection and Removal
• Utility Programs to
• Intercept incoming, and outgoing email
• Scanning existing files for malware presence
• Looking for known offenders
• Repair / quarantine

There are thousands
Scan all potentially dangerous files
Scanning is a lengthy process
For ALL known signatures
Pop-up removal utilities will intercept known
pop-ups
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Malware Detection/Removal S/W
Findings
Detection/Removal SoftWare
Researchers (the CIA)
Information Sources

• Each group has
• Their focus items
• Their informational sources
• Therefore
• You will need to install multiple products -
  Anti-Virus, Spyware removal, etc
• And maybe more than one of each.

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Why Cant I Open The Email Attachment Or A
Discussion About File Assocoations
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3 Different Ways to Start Programs

• From the Start Menu or Desktop Icon
• By dropping a file on an application icon
• By clicking on a file e.g. a Word document

Lets look at that happens with 3
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File Types and Associations

• There are 100s of different file types
• .doc for MS Word documents
• .pdf for Acrobat Reader files
• .ppt for PowerPoint file
• Etc.
• You dont have to use these designations if you
  dont what to!
• Just because you add the .doc , for e.g, to a
  document doesnt make it a Microsoft Word
  document. The application still need to
  understand the format

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File Types and Associations

• BUT
• Windows has something called File Associations
• Files Association is a list of different file
  types with the default application used with that
  file type.
• When you install a application, The installation
  will update the File Association Table
• Sometime that is not desirable by the way!
• So when you click on the file this is what
  happens

Open Selected File
Start MS Word
Click
Doc MS Word
Determine Default Application
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File Types and Associations
When you click on an email attachment or open a
file on a webpage the same actions occur.
Open Selected File
Start MS Word
Click
Doc MS Word
Determine Default Application
If Windows cant find an association it will then
prompt you to specify what application you would
like to use.
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File Types and Associations

• Windows will give you a list of possible
  applications.
• - You would choose the appropriate
  application
• If the application is not there you need to
• Find the correct application by browsing
• Installing the correct application
• Send a message to the sender saying you dont the
  application maybe they can send it another
  format i.e. a rtf instead of a lwb (Lotus
  WordPro)
• What happens if the wrong application is started
• You can modify the File Associations
• Much simpler with XP in fact the whole area of
  file associations is much better with XP.

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Time for Your Questions? But first we will ask
Mike to show us how to read an email without
opening it.