1. Chapter 2 Desktop Security
Security Awareness: Applying Practical Security in Your World, Second Edition
Chapter 2
Desktop Security

2. Objectives
Describe the type of attacks that are launched against a desktop computer
List the defenses that can be set up to protect a desktop computer
Describe the steps for recovering from an attack
Security Awareness: Applying Practical Security in Your World, 2e

3. Attacks on Desktop Security
Malicious software (malware)
Can break into and create havoc on desktop computers
Internet service providers (ISPs) in North America
Spend $245 million annually to combat malware
Virus
Secretly attaches itself to document or program and executes when document or program is opened
Security Awareness: Applying Practical Security in Your World, 2e

4. Security Awareness: Applying Practical Security in Your World, 2e

5. Viruses Require a host to carry them from one system to another
Possible effects
Cause a computer to continually crash
Erase files from a hard drive
Install hidden programs
Reduce security settings
Reformat the hard disk drive
Security Awareness: Applying Practical Security in Your World, 2e

6. Viruses (continued) Symptoms that indicate virus infection
Program suddenly disappears from computer
New programs do not install properly
Out-of-memory error messages appear
Unusual dialog boxes or message boxes appear
Computer runs slowly and takes a long time to start
Significant amount of modem activity
Security Awareness: Applying Practical Security in Your World, 2e

7. Worms Difference between worms and viruses Virus Worm
Must attach itself to a computer document
Spreads by traveling along with the document
Requires action by computer user to begin execution
Worm
Does not attach to a document to spread
Can travel by itself
Needs user to perform an action
Security Awareness: Applying Practical Security in Your World, 2e

8. Logic Bombs
Computer programs that lay dormant until triggered by a specific logical event
Once triggered
Can perform various malicious activities
Extremely difficult to detect before triggered
Security Awareness: Applying Practical Security in Your World, 2e

9. Basic Attacks Social engineering Password guessing
Physical theft or lost data
Improper use of recycled computers
Security Awareness: Applying Practical Security in Your World, 2e

10. Social Engineering
Relies on tricking and deceiving someone to access a system
Dumpster diving
Digging through trash receptacles to find
Computer manuals
Printouts
Password lists
Security Awareness: Applying Practical Security in Your World, 2e

11. Password Guessing Password Characteristics of weak passwords
Secret combination of letters and numbers that validates or authenticates a user
Characteristics of weak passwords
Passwords that are short
Common word used as a password
Using the same password for all accounts
Personal information in a password
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12. Security Awareness: Applying Practical Security in Your World, 2e

13. Password Guessing (continued)
Brute force
Attacker attempts to create every possible password combination
Dictionary attack
Attacker takes each word from dictionary and encodes it
Attacker then compares the encoded dictionary words against those in the encoded password file
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14. Security Awareness: Applying Practical Security in Your World, 2e

15. Physical Theft or Lost Data
February 2005
Bank of America lost computer backup tapes
Containing personal information on about 1.2 million charge card users
May 2005
AOL reported that information on 600,000 current and former employees was missing
June 2005
Citigroup announced that personal information on 3.9 million consumer lending customers of its CitiFinancial subsidiary was lost or stolen
Security Awareness: Applying Practical Security in Your World, 2e

16. Improperly Recycled Computers
Many organizations and individuals recycle older computers by giving them to schools, charities, or selling them online
Deleting files does not remove the information
Only deletes filename from hard disk table
Even reformatting a drive, or preparing the hard drive to store files, may not fully erase data on it
Security Awareness: Applying Practical Security in Your World, 2e

17. Desktop Defenses Patch software Microsoft Windows operating system
Software security updates
Microsoft Windows operating system
Most frequently distributed patch software
Microsoft
Releases patches on second Tuesday of every month
Typically releases 5-15 software patches for download and installation
Security Awareness: Applying Practical Security in Your World, 2e

18. Desktop Defenses (continued)
Microsoft classifies patches based on level of vulnerability that patch fixes
Critical
Important
Moderate
Low
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19. Desktop Defenses (continued)
Update configuration options
Automatic
Download
Notify
Turnoff
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20. Security Awareness: Applying Practical Security in Your World, 2e

21. Antivirus Software Best defense against viruses
Generally configured to
Constantly monitor for viruses
Automatically check for updated signature files
Allows for manual signature updates
Security Awareness: Applying Practical Security in Your World, 2e

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24. Strong Authentication Methods
Basic rules for creating strong passwords
Passwords must have at least eight characters
Passwords must contain a combination of letters, numbers, and special characters
Passwords should be replaced every 30 days
Passwords should not be reused for 12 months
Same password should not be used on two or more systems or accounts
Security Awareness: Applying Practical Security in Your World, 2e

25. Security Awareness: Applying Practical Security in Your World, 2e

26. Strong Authentication Methods (continued)
Biometrics
Uses unique human characteristics for authentication
Most common biometric device
Fingerprint scanner
High-end scanners
Relatively expensive
Can be difficult to use
Can reject authorized users while accepting unauthorized users
Security Awareness: Applying Practical Security in Your World, 2e

27. Security Awareness: Applying Practical Security in Your World, 2e

28. Protecting Laptop Computers
Device lock
Consists of a steel cable and a lock
Economical, simple and quick to install
Very portable
Stealth signal transmitter
Software installed on laptop that cannot be detected
Security Awareness: Applying Practical Security in Your World, 2e

29. Security Awareness: Applying Practical Security in Your World, 2e

30. Cryptography Science of transforming information
So that it is secure while being transmitted or stored
Does not attempt to hide the existence of data
Scrambles data so that it cannot be viewed by unauthorized users
Security Awareness: Applying Practical Security in Your World, 2e

31. Cryptography (continued)
Encryption
Changing original text to secret message using cryptography
Decryption
Changing secret message back to its original form
Security Awareness: Applying Practical Security in Your World, 2e

32. Public and Private Keys
Private key system
Same key is used to encrypt and decrypt message
Public key system
Two mathematically related keys are used
Public key and a private key
Security Awareness: Applying Practical Security in Your World, 2e

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34. Security Awareness: Applying Practical Security in Your World, 2e

35. Digital Signatures Digital signature
Code attached to an electronic message that helps to prove that
Person sending message with public key is not an imposter
Message was not altered
Message was sent
Encrypted hash of a message that is transmitted along with message
Security Awareness: Applying Practical Security in Your World, 2e

36. Digital Signatures (continued)
Hash
Creates encrypted text that is never intended to be decrypted
Used in a comparison for authentication purposes
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39. Digital Certificates Link or bind a specific person to a public key
Provided by a certification authority (CA)
Public key that has been digitally signed by a recognized authority (the CA)
Attesting that owner of the key is not an imposter
Security Awareness: Applying Practical Security in Your World, 2e

40. Properly Retiring Old Computers
Files that should be removed when selling or donating an old computer
contacts
messages
All personal documents
All files in the recycle bin or trash folder
Internet files
All nontransferable software
Security Awareness: Applying Practical Security in Your World, 2e

41. Recovering from Attacks
Major steps to take when preparing for an attack
Back up your data
Back up system information
Creating a data backup involves
Copying data onto digital media
Storing it in a secure location
Security Awareness: Applying Practical Security in Your World, 2e

42. Recovering from Attacks (continued)
Questions when creating a data backup
What information should be backed up?
How often should it be backed up?
What media should be used?
Where should the backup be stored?
How should the backup be performed?
Security Awareness: Applying Practical Security in Your World, 2e

43. Saving Automated System Recovery (ASR) Data
Windows XP Automated System Recovery (ASR)
Includes an ASR backup and ASR restore
ASR backup records
System state
System services
All disks associated with operating system components
Security Awareness: Applying Practical Security in Your World, 2e

44. Restoring the Computer
To recover from an attack using ASR
Insert original operating system installation CD into the CD drive
Restart computer
Press the F2 key when prompted
Insert the ASR floppy disk when prompted
Follow remaining directions on the screen
Security Awareness: Applying Practical Security in Your World, 2e

45. Clean up the Attack Microsoft Windows Malicious Software Removal Tool
Helps remove infections by specific malware
When done, displays a report describing outcome
Security Awareness: Applying Practical Security in Your World, 2e

46. Restore Data from Backups
Most vendors
Provide an automated wizard that guides user through process of restoring files
After any successful attack
Analyze why attack got through defenses
Security Awareness: Applying Practical Security in Your World, 2e

47. Summary Malicious software Social engineering Patch software
Programs designed to break into or create havoc on desktop computers
Social engineering
Relies on trickery and deceit
Is considered a basic attack
Patch software
Describes software security updates
Security Awareness: Applying Practical Security in Your World, 2e

48. Summary (continued) Strong passwords
Important defense mechanism against attackers
Important to perform regular data backups
If a computer becomes infected with malware
Remove computer from network
Try to reboot computer
Security Awareness: Applying Practical Security in Your World, 2e