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Understanding Network Security and Cyber Attacks

Learn why understanding cyber attacks is crucial, explore a security breach example, grasp the attacker's process, and discover how to protect your network. Understand the importance of information gathering and steps to secure your system effectively.

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Understanding Network Security and Cyber Attacks

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Presentation Transcript

  1. SYP: Network Security

  2. Security • Why is it important to understand how attacks work ? • Golden Age of Hacking • How bad is the problem? • How did this happen?

  3. Security Breach Example • 2003 group of hackers were “testing” security of various banks and noticed that one was extremely vulnerable • Within a couple of hours, they transferred over $10 million dollars from the bank to a private account • Due to bank’s poor network security, attackers tracks were difficult to find • To ensure no prosecution, hackers contacted bank president and gave two options: • Bank could prosecute, but attackers would deny everything and notify media on bank’s poor security • Sign proposal indicating that hacker’s were forming a security assessment at bank’s request for $5 million dollars and hackers would then return the other $5 million. • What choice do you think the bank president chose?

  4. Organizational Problems • Why companies don’t report attacks • Ignorance • Bad publicity • Cost and ineffectiveness of Fixing Existing Systems • Intangible Nature of Security Benefits

  5. The Attacker’s Process • Many ways an attacker can gain access or exploit a system • Some basic steps that hackers follow: • Passive reconnaissance • Active reconnaissance (scanning) • Exploiting the system • Uploading programs • Downloading data • Keeping access by using backdoors and trojan horses • Covering tracks

  6. Passive Reconnaissance • To exploit a system an attacker must have some general information about the user or company • Information gathering • Sniffing

  7. Active Reconnaissance • At this point, an attacker has enough information to try active probing or scanning against a site. • Key information that an attacker will try to discover: • Hosts that are accessible • Locations of routers and firewalls • Operating systems running on key components • Ports that are open • Services that are running • Versions of applications that are running

  8. Exploiting the System • 3 areas to exploit on a system: • Gaining access • Operating system attacks • Application-level attacks • Scripts and sample program attacks • Misconfiguration attacks • Elevation of privileges • Denial of service

  9. Uploading and Downloading Programs • After an attacker has gained access, they usually perform some set of actions on the server. • Most often, hacker will load some programs to the system. • With some attacks, such as corporate espionage, an attacker is after information

  10. Keeping Access • Most cases, after attacker gains access to a system, he will put a back door so that he can return whenever he wants. • Basic back door: are highly detectable • Sophisticated back door: more difficult to detect • Gaining access to the system and create a back door simultaneously

  11. Covering Tracks • After an attacker compromises a machine and creates a back door, the last thing he does is make certain that he does not get caught • Clean up log files • Turn off logging • To protect against hackers – use a program that makes sure key files on the system have not been changed

  12. Information Gathering

  13. Information Gathering • Many companies only concentrate on protecting their systems from a specific exploit when they start building a security infrastructure • Key for a user or organization to know what information an attacker can acquire about them and minimize the potential damage • If the attacker can only gain limited information about the network, they will most likely move on to the next victim

  14. Step 1 Gathering Initial Information • Find out initial information: • Open Source • Whois • Nslookup

  15. Step 2: Discover address range of the network • Find out address range of the network: • ARIN (American Registry for Internet Numbers) • Traceroute

  16. Step 3 Discovering Active Machines • Find active machines: • Ping

  17. Step 4Find Open Ports or Access Points • Applications used to find open ports or access points: • Portscanners • Nmap • ScanPort • War Dialers • THC-Scan

  18. Step 5Figure Out the Operating System • Tools used to determine Operating Systems • Queso • Nmap

  19. Step 6: Figure Out Which Services are Running on Each Port • Tools used to determine which services are running on each port • Default port and OS • Telnet • Vulnerability scanners

  20. Step 7 Map Out the Network • Tools used to map out the network • Traceroute • Visual Ping • Cheops

  21. Spoofing

  22. Types of Spoofing • Types of Spoofing Techniques • IP Spoofing • Email Spoofing • Web Spoofing • Non-Technical Spoofing

  23. IP Spoofing • Basic Address Change • Protection Against Address Changes

  24. IP Spoofing Continued • Source Routing • Allows you to specify the path a packet will take through the Internet • Types: • Loose Source Routing (LSR) • Strict Source Routing (SSR) • Protection Against Source Routing

  25. IP Spoofing Continued • Trust Relationships • Protection Against Trust Relationships

  26. EMAIL Spoofing • Similar Email Address • Protection Against Similar Email Address

  27. EMAIL Spoofing • Modifying a Mail Client • Protection Against Modifying a Mail Client

  28. EMAIL Spoofing • Telnet to Port 25 • Protection Against Telnetting to Port 25

  29. Web Spoofing • Basic Web Spoofing • Protection Against Basic Web Spoofing

  30. Web Spoofing • Man-in-the-Middle Attacks • Protection Against Man-in-the-Middle Attacks

  31. Web Spoofing • URL Rewriting • Protection Against URL Rewriting From Anonymizer.com

  32. Web Spoofing Tracking State: • Cookies • Protection Against Cookies

  33. Web Spoofing Tracking State: • URL Session Tracking • Protection Against URL Session Tracking

  34. Web Spoofing Tracking State: • Hidden Form Elements • Protection Against Hidden Form Elements

  35. General Web Spoofing Protection • Disable JavaScript, ActiveX, etc. • Validate that application is properly tracking users • Make certain users can’t customize their browsers to display important information • Educate the users • Make certain that any form of ID used to track user is long and random

  36. Non-Technical Spoofing • Social Engineering • Reverse Social Engineering • Non-Technical Spoofing Protection

  37. Denial of Service (DOS)

  38. What is a DOS Attack? • Attack through which a person can render a system unusable or significantly reduced by overloading the system’s resources • DOS attacks can be intentional or accidental • Often used by an attacker if they are unable to gain access to a network or machine

  39. Some Types of DOS Attacks • Ping of Death • SSPing • Smurf • CPU Hog

  40. Password Security

  41. Typical Attack • Two of the most common weaknesses on computer systems: • Weak Passwords • Modems

  42. Current State of Passwords • Current state of passwords in most companies and home systems are poor • Software often has default passwords that are rarely changed • Passwords are often chosen that are trivial to guess or have no password at all • Password intervals are too long

  43. History of Passwords • Users often choose simple passwords • Wife’s name • Favorite sport • Date of user’s birthday • Complex passwords are often written down since they are difficult to remember • Ex: W#hg@5d4%d10

  44. Future of Passwords • Single Sign On (SSO) • One password for user’s various applications • Biometrics • Fingerprint scan • Hand scan • Retinal scan • Facial scan • Voice scan

  45. Strong Passwords • Subject to technology • Strong Password criteria: • Changes every 45 days • Minimum length of 10 characters • Must contain at least on alpha, one number, and one special character • Alpha, number, and special characters must be mixed up and not append to the end • Ex: abdheus#7 = Bad • Ex: fg#g3^hs5gw = Good • Cannot contain dictionary workds • Cannot reuse previous five passwords • Minimum password age of 10 days • After 3 failed logon attempts, password is locked for several hours

  46. Why is Password Cracking Important? • To audit the strength of passwords • To recover forgotten/unknown passwords • To migrate users • To use a checks and balance system

  47. Types of Password Attacks • Dictionary Attacks • Brute Force Attacks • Hybrid Attacks • Social Engineering Attacks

  48. SecuringMicrosoft Passwords

  49. Where Are Passwords Stored in Microsoft? • Password hashes for each account are stored in the Security Account Manager (SAM) • \Windows-directory\system32\config\SAM • \Windows-directory\repair

  50. How Does MS Encrypt Passwords? • 2 hash algorithms • One for regular NT hash • MD4 hash algorithm • One for LANMAN hash • Pad password with 0’s to equal 14 character • Combined to attain 16-byte hash value

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