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WARNING !

WARNING !. The system is either busy or has been unstable. You can wait and See if it becomes available again, or you can restart your computer. * Press any key to return to Windows and wait. * Press CTRL+ALT+DEL again to restart your computer. You will

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  1. WARNING ! • The system is either busy or has been unstable. You can wait and • See if it becomes available again, or you can restart your computer. • * Press any key to return to Windows and wait. • * Press CTRL+ALT+DEL again to restart your computer. You will • Lose unsaved information in any programs that are running. • Press any key to continue.

  2. Group 4 Presents: Carl the Happy Chatter But not for long…. Carl Morris Andrew Snyder Ken Nguyen Dec 4 2000 User Attacks

  3. User Attacks What is it? • An attack mounted against an end user of the Internet Goals of an attacker • Obtain access to systems • Eavesdrop on communications • Aggravate and annoy a household user • Cause damage! Anything to annoy an end user

  4. Context of Discussion • Not meant to apply to “computer geeks” • Applies to average end user • Attacks mounted easily by attackers with limited computer knowledge

  5. Methods of choice • Performed a search for phrases such as “How to find Windows NT passwords,” “Hacking into Computers” & “Easy Hacking” • Used our own past experiences (world & class) • Our own interests

  6. We decided... • The Big Three: • Denial of Service (DoS) • Packet Sniffing • Back Orifice 2000

  7. What is DoS? • Attacker consumes limited resources on victim’s machine • CPU time • memory • bandwidth

  8. DoS • Easy DoS Attack • Ping Flooding • Ping of Death • WinNuke

  9. Ping Flooding • What is Ping Flooding? • Sending huge amounts of ICMP Echo Requests • Used legitimately to test your connection

  10. Ping Flooding (cont.) • Ping Flooding’s impact • Ties up victim’s bandwidth • Forces dialup users to disconnect • May cause victim’s machine to crash

  11. Ping Flooding (cont.) • Ping Flooding is Hard! • Need to know victim’s IP • Easily obtained from ICQ, IRC, message forums, etc... • Must type “ping destination_IP –t –l huge#”

  12. Ping of Death • What is Ping of Death? • Carl receives a packet of illegal size • Carl’s computer crashes 

  13. Ping of Death (cont.) • Ping of Death is also very hard • Must type “ping destination_IP –l 65550”

  14. WinNuke • What is WinNuke? • Takes advantage of Window’s Out of Band (OOB) bug • Carl receives a pointer that is invalid • Carl’s computer crashes 

  15. WinNuke • WinNuke is also very hard

  16. Protect yourself • Ping of Death & WinNuke • Get patches for your appropriate OS to prevent overflow/pointer error

  17. Protect yourself • Ping Flooding • Sets computer not to echo back, cuts by 50% • Call your ISP, or set up your own firewall • Stop it before it start: Do not give out your IP!

  18. What Is Packet Sniffing? • Packet sniffing is eavesdropping on network traffic. • It consists of capturing packets on the network and analyzing them to obtain information.

  19. What Is in a Packet? • Source and Destination (MAC) • A packet can contain information ranging from web addresses to passwords. • However, it is all in binary form, and requires a protocol analyzer to make sense of it all.

  20. MAC • Each Ethernet card contains a 48-bit identifier – Media Access Control • The first 24 bits identify the vendor • The last 24 bits identify the card • To find out your MAC: Win9x – winipcfg.exe WinNT – ipconfig /all Linux – ifconfig

  21. How Is Packet Sniffing Used? • Packets are captured. -- Promiscuous mode • Packets are analyzed. -- Protocol analyzer (LanSleuth, Neptune, Ethereal)

  22. Malicious Effects • Websites • Passwords • Any unencrypted information sent over the network (Messages, Files)

  23. Ease of Use • Network Protocol Analyzers LanSleuth, Ethereal, Neptune, snoop • Easy installation and configuration • Some analyzers require administrative permissions

  24. Examples • Packet captured using Ethereal

  25. Analyzing • Packet entered into Ethereal Decode

  26. Preventions • Encrypt all transfers SSL – Secure Socket Language SSH – Secure Shell VPN – Virtual Private Networks

  27. Detections • In theory – impossible • In practice – possible sometimes • Stand-alone packet sniffers don’t transfer packets • Non-standard generate traffic (DNS reverse lookups in order to find names associated with IP addresses)

  28. Ping Method • Send a request • Nobody should respond • Response --> Sniffer!

  29. Packet Sniffing Re-visited • Packets are “captured” on the network • They are then analyzed - Passwords - Web sites • Impossible to stop • Difficult to detect

  30. Back Orifice 2000 What is it? “The most powerful network administration tool available for the Microsoft environment” How is it used? • An “administrator” • creates a custom server file • installs this server on the target machine • connects to the target machine • perform various functions

  31. Back Orifice 2000 Malicious effects A malicious attacker can: • Install the server on victim’s machine • Take over computer • Logging keystrokes • Rebooting • Viewing • cached passwords • the active screen • etc Ease of use • In the next few minutes, I will show you how to use BO2K

  32. Back Orifice 2000 Create a server file…

  33. Back Orifice 2000 Create a server file… (continued)

  34. Back Orifice 2000 Time to connect

  35. Back Orifice 2000 Some stuff…

  36. Back Orifice 2000 Plugins • Encryption (AES, IDEA, RC6, Serpent) • Communications • Server Enhancement • Client Enhancement

  37. Back Orifice 2000 BO Peep Plugin

  38. Back Orifice 2000 BO Tools Plugin

  39. Prevention Measures Umgr32.Exe anyone ? 1) Antivirus 2) firewall 3) don’t trust anyone 4) look for umgr32.Exe (or registry) on your computer 5) Microsoft: get a clue

  40. Summary • Many user attacks are so easy that even your mom could figure them out • Some attacks can’t be protected against based on current network protocol and system architecture • Microsoft needs to tighten up security on their products

  41. Conclusion • Are you safe? • That kid next door could be screwing with you right now. • You could be a victim of user attacks and not even know it. • Practice online safety measures. • You are not invincible: Don’t take security for granted

  42. Questions

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