23 computer security
- 2. Computer Security Through your PC, a malicious person can gain valuable information – About you and your habits – Can steal your files – Run programs that log your keystrokes and thus gain account names and passwords, credit card information – Run software that takes over much of your computer processing time and use it to send spam or steal from others
- 3. Analyzing the Threat Threats to your data and PC come from two directions: – Mistakes – Malicious people Issues: – Unauthorized access – Data destruction, accidental or deliberate – Administrative access – Catastrophic hardware failures – Viruses/spyware
- 4. Local Control Need to establish control over local resources – Back up data and make sure that retired hard drives and optical discs have no sensitive data on them – You should recognize security issues and be able to respond properly – You need to implement good access control policies, such as having All computers in your care locked down with proper passwords or other devices that recognize who should have access Implement methods for tracking computer usage. – If someone is doing something wrong, you and the network or computer administrator should be able to catch him or her! Backup Essential Data
- 5. Social Engineering The process of using or manipulating people inside the networking environment to gain access to that network from the outside The term “social engineering” covers the many ways humans can use other humans to gain unauthorized information
- 6. Infiltration Hackers can physically enter your building under the guise of someone who might have a legitimate reason for being there, – Cleaning personnel, repair technicians, or messengers
- 7. Telephone Scams Telephone scams are probably the most common social engineering attack The attacker makes a phone call to someone in the organization to gain information
- 8. Dumpster Diving Generic term for anytime a hacker goes through your refuse (rubbish), looking for information
- 9. Physical Theft Someone physically steal the server
- 10. Access Control Control access to the data, programs, and other computing resources
- 11. Secure Physical Area and Lock Down Your System Block access to the physical hardware from people who shouldn’t have access
- 12. Authentication Means How the computer determines – Who can or should access it – Once accessed, what that user can do A computer can authenticate users through – Software or hardware – Combination of both
- 13. NTFS, Not FAT32 Must use NTFS or you have no security at all Use the CONVERT command-line utility to go from FAT to NTFS – CONVERT D: /FS:NTFS
- 14. Network Security User Account Control Through Groups Security Policies Commonly used: – Prevent Registry Edits If you try to edit the Registry, you get a failure message – Prevent Access to the Command Prompt This policy keeps users from getting to the command prompt by turning off the Run command and the MS-DOS Prompt shortcut – Log on Locally This policy defines who may log on to the system locally – Shut Down System This policy defines who may shut down the system – Minimum Password Length This policy forces a minimum password length – Account Lockout Threshold This policy sets the maximum number of logon attempts a person can make before they are locked out of the account – Disable Windows Installer This policy prevents users from installing software – Printer Browsing This policy enables users to browse for printers on the network, as opposed to using only assigned printers
- 15. Viruses A computer virus is a piece of malicious software that gets passed from computer to computer A computer virus is designed to attach itself to a program on your computer – It could be your e-mail program, your word processor, or even a game – Whenever you use the infected program, the virus goes into action and does whatever it was designed to do – It can wipe out your e-mail or even erase your entire hard drive! Viruses are also sometimes used to steal information or send spam e-mails to everyone in your address book
- 16. Virus Trojans Worms Polymorphics/Polymorphs Stealth
- 17. Antivirus Programs Protects your PC in two (2) ways It can be both sword and shield – Working in an active seek-and-destroy mode – A passive sentry mode
- 18. Spam E-mail that comes into your Inbox from a source that’s not a friend, family member, or colleague, and that you didn’t ask for Pop-ups Spyware Adware
- 19. Firewalls Devices or software that protect an internal network from unauthorized access to and from the Internet at large Hardware firewalls protect networks using a number of methods, such as hiding IP addresses and blocking TCP/IP ports Windows XP comes with an excellent software firewall – Windows Firewall
- 20. Encryption Stop someone to intercept and inspect the packet Inspected packets are a cornucopia of – Passwords – Account names – Other tidbits that hackers can use to intrude into your network
- 21. Network Authentication PAP Password Authentication Protocol (PAP) – Is the oldest and most basic form of authentication – It’s also the least safe, because it sends all passwords in clear text – No NOS uses PAP for a client system’s login, but almost all network operating systems that provide remote access service will support PAP for backward compatibility with a host of older programs (like Telnet) that only use PAP
- 22. Network Authentication CHAP Challenge Handshake Authentication Protocol (CHAP) is the most common remote access protocol CHAP has the serving system challenge the remote client – A challenge is where the host system asks the remote client some secret—usually a password that the remote client must then respond with for the host to allow the connection
- 23. Network Authentication MS-CHAP MS-CHAP is Microsoft’s variation of the CHAP protocol. It uses a slightly more advanced encryption protocol
- 24. Data Encryption Encryption methods don’t stop at the authentication level There are a number of ways to encrypt network data as well IPSec (IP Security) – Provides transparent encryption between the server and the client – Also work in VPNs, but other encryption methods are more commonly used in those situations
- 25. Application Encryption Famous of all application encryptions is Netscape’s Secure Sockets Layer (SSL) – Protocols make it possible to create the secure Web sites used to make purchases over the Internet – HTTPS Web sites can be identified by the HTTPS:// included in their URL
- 26. Wireless Issues Set up wireless encryption, at least WEP but preferably WPA or the more secure WPA2, and configure clients to use them Disable DHCP and require your wireless clients to use a static IP address If you need to use DHCP, only allot enough DHCP addresses to meet the needs of your network to avoid unused wireless connections Change the WAP’s SSID from default and disable SSID broadcast Filter by MAC address to allow only known clients on the network Change the default user name and password. Every hacker has memorized the default user names and passwords Update the firmware as needed If available, make sure the WAP’s firewall settings are turned on
- 27. Reporting Event Viewer Auditing
- 28. Incidence Reporting First – It provides a record of work you’ve done and accomplished Second – It provides a piece of information that when combined with other information that you might or might not know, reveals a pattern or bigger problem to someone higher up the chain