1 / 15

Network Assessment

How intrusion techniques contribute to system/network security Network and system monitoring System mapping Ports, OS, applications and purpose Network mapping Legal issues. Network Assessment. Network Monitoring. General Purpose Functions Applications Design

yaholo
Download Presentation

Network Assessment

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. How intrusion techniques contribute to system/network security Network and system monitoring System mapping Ports, OS, applications and purpose Network mapping Legal issues Network Assessment

  2. Network Monitoring • General • Purpose • Functions • Applications • Design • NIDS – Network Intrusion Detection • IPS – Intrusion Prevention System

  3. Network and System Scanning • What application versions are running? • What services are running? • What ports/services are open? • What does the network look like? • What can the external world see? • Have any of these changed?

  4. Network Assessment • What do the other systems look like? • What does my system look like to outsiders? • Remote system characterization • LAN topology • Tools • nmap • nessus

  5. Network Assessment • Planning • Initial reconnaissance • System enumeration • Service enumeration • Vulnerability discovery

  6. Planning • Appropriate time • You will probably crash operational systems • You will need admin support • Approximate possible risks • Determine costs – man hours • Management written approval • Make sure every one buys into what you are doing

  7. Initial Reconnaissance • Corporate structure • Web surfing • Web browser • www.copernic.com • whois • host • NetScanTools Pro • DNS information • nslookup • DNS information • Should return minimal info if well configured

  8. System Enumeration • Using information from initial reconn phase • Discover more hosts and servers • Perimeter defense may block some scans • Directly probe target network • Combine discovery and analysis techniques • Structure of network • Perimeter design

  9. Tools • traceroute • The important info for this phase • Target routers and DNS servers • What is the route form a server to the Internet • Often server names give geographic or organizational info

  10. Tools • Network scanners • ICMP – fping and pinger • Looks for systems that return ICMP messages • TCP, UDP – nmap • Searches the entire range of IP addresses allocated to a network

  11. Service Enumeration • Now find out what is available on each system • Services • Ports open, ports filtered, OS • Application versions • System policies • Password policy • Users, domains, system names

  12. Tools • nmap • LANGuard • ww.gfisoftware.com/languard/lanscan.htm • Used as a LAN audit tool, $249 • Telnet and banner retrieval :\>telent sou.edu 22 SSH-1.99-OpenSSH_3.1p1 :\>telent www.sou.edu 80 HEAD / HTTP/1.0 HTTP/1.1 50` Method not implemented Date: Sun, 02 Mar 2003 20:46:44 GMT Server: Apache/1.3.27 (Unix) (Red Hat/Linux mod_ssl/2.8.12 OpenSSL/0.9.6 DAV/1.0.2 PHP/4.1.2 mod_perl/1.24

  13. Vulnerability Discovery • Vulnerability scanners • Work at the application layer • Most of these scanners also do network and port scanning • Best to start from the beginning • Network enumeration, System enumeration, Vulnerability discovery

  14. Vulnerability Discovery • Tools • Nessus – open sourced, very complete • ISS Internet Scanner – Windows, $$ • Retina – Windows, good GUI, $$

  15. Summary • Network assessment • CAREFUL • This is ILLEGAL

More Related