1 HoneyNets, Intrusion Detection Systems, and Network Forensics

ECE 4112-Internetwork Security2 Introduction Definition of a Honeynet Concept of Data Capture and Data Control Generation I vs. Generation II Honeynets Description of the Georgia Tech Campus Network Current Vulnerabilities on the Internet Current Tools to Protect Networks  Firewalls  Intrusion Detection Systems (IDS)

ECE 4112-Internetwork Security3 Shortcomings Associated with Firewalls 1. The firewall cannot protect against attacks that bypass it, such as a dial–in or dial-out capability. 2. The firewall at the network interface does not protect against internal threats. 3. The firewall cannot protect against the transfer of virus–laden files and programs

ECE 4112-Internetwork Security4 Shortcomings Associated with Intrusion Detection Systems 1.Increase Complexity of Security Management of Network 2.High Level of False Positive and False Negative Alerts 3.Must Know Signature or Anomoly Detection Pattern

ECE 4112-Internetwork Security5 Definition of a Honeynet Network Established Behind a Reverse Firewall Captures All In-Bound and Out-Bound Traffic Any Type of System Network is Intended To Be Compromised All Honeynet traffic is suspicious

ECE 4112-Internetwork Security6 Data Capture and Data Control Data Capture  Collect all information entering and leaving the Honeynet covertly for future analysis Data Control  Covertly protect other networks from being attacked and compromised by computers on the Honeynet

ECE 4112-Internetwork Security7 Generation I vs. Generation II GEN I Honeynet  Simple Methodology, Limited Capability  Highly effective at detecting automated attacks  Use Reverse Firewall for Data Control  Can be fingerprinted by a skilled hacker  Runs at OSI Layer 3 GEN II Honeynet  More Complex to Deploy and Maintain  Examine Outbound Data and make determination to block, pass, or modify data  Runs at OSI Layer 2

ECE 4112-Internetwork Security8 Georgia Tech Campus Network Students, 5000 Staff, 69 Departments networked computers on campus Average data throughput 600Mbps/4 terabytes per day NO FIREWALL BETWEEN CAMPUS & INTERNET!  Why? Requirement for Academic Freedom, high throughput  However, individual enclaves within Georgia Tech use firewalls IDS is run at campus gateway  Out of band monitoring and follow-on investigation

ECE 4112-Internetwork Security9 Establishment of the Honeynet on the Georgia Tech Campus Established in Summer of 2002 Uses Open Source Software Initially Established As One Honeynet Machine behind the firewall IP Address Range Provided by Georgia Tech Office of Information Technology (OIT)

ECE 4112-Internetwork Security10 Georgia Tech Honeynet

ECE 4112-Internetwork Security11 Hardware and Software No Requirement for State of the Art Equipment (Surplus Equipment) No Production Systems Minimum Traffic Use Open Source Software (SNORT, Ethereal, MySQL DB, ACID) Use Reverse Firewall Script Developed by Honeynet.org

ECE 4112-Internetwork Security12 Intrusion Detection System Used with HoneyNet SNORT  Open Source  Signature-Based, with Anomaly-Based Plug-in Available  Can Write Customized Signatures Run Two Separate SNORT Sessions  One Session to Check Against Signature Database  One Session to Capture All Inbound/Outbound Traffic

ECE 4112-Internetwork Security13 Analysis Console for Intrusion Detection (ACID)

ECE 4112-Internetwork Security14 Logging and Review of Data Honeynet Data is stored in two separate locations  Alert Data is stored in SQL database  Packet Capture Data is stored in a daily archive file Data Analysis is a time consuming process In our Experience:  One hour/day to analyze traffic  One hour of attack traffic can result up to one week of analysis

ECE 4112-Internetwork Security15 Ethereal Analysis Tool

ECE 4112-Internetwork Security16 Exploitations Detected on the Georgia Tech Honeynet 36 possible exploited machines have been detected at Georgia Tech in previous 9 months (through June 2003) A report is made to OIT on each suspected compromise

ECE 4112-Internetwork Security17 Identification of a System with a Compromised Password Previously Compromised Honeynet Computer Continued to Operate as Warez Server Another Georgia Tech Computer Connected to the Warez Server Investigation Revealed that Password had been Compromised on Second Georgia Tech Computer

ECE 4112-Internetwork Security18 Detection of Worm Type Exploits GEN I Honeynet Well-Suited to Detect Worm Type Exploits  Repeated Scans targeting specific ports  Analyze captured data for time lapses Ability to Deploy Specific Operating System on Honeynet

ECE 4112-Internetwork Security19 Exploitation Pattern of Typical Internet Worm Target Vulnerabilities on Specific Operating Systems Localized Scanning to Propagate (Code Red)  3/8 of time within same /16 network  1/2 of time within same /8 network  1/8 of time random address Allows for Quick Infection Within Internal Networks with High Concentration of Vulnerable Hosts

ECE 4112-Internetwork Security20 Georgia Tech Honeynet Gen II

ECE 4112-Internetwork Security21 Initial Observations of Gen II Honeynet Configuration is more complex than Gen I Must use variants of Linux 2.4 kernel in order to run Sebek keystroke logger capability Data must continue to be monitored on a daily basis

ECE 4112-Internetwork Security22 Honeynet Portscan Activity Date Public: 7/24/02 Date Attack: 1/25/03

ECE 4112-Internetwork Security23 Honeynet Portscan Activity Date Public: 7/16/03 Date Attack: 8/11/03

ECE 4112-Internetwork Security24 Honeynet Portscan Activity Date Public: 8/15/2003 Date Attack: 8/22/03

ECE 4112-Internetwork Security25 Conclusions on HoneyNets Honeynet Assists in Maintaining Network Security Provides Platform for Research in Information Assurance and Intrusion Detection

ECE 4112-Internetwork Security26 IDS - Purpose Misuse detection Anomaly detection Conduct forensics Network traffic recording and analysis Intellectual property protection

ECE 4112-Internetwork Security27 IDS Strategies Signature-based (misuse detection)  pattern matching  cannot detect new attacks  low false positive rate Anomaly-based (statistical-based)  activity monitoring  has the ability to detect new attacks  higher false positive rate

ECE 4112-Internetwork Security28 IDS Deployment Network-based  Inspect network traffic  Monitor user activity (packet data) Host-based  Inspect local network activity  OS audit functionality  Monitor user activity (function calls)

ECE 4112-Internetwork Security29 Example IDS:Snort Sniffer Packet logger IDS

ECE 4112-Internetwork Security30 Snort Rules Example 1: “log tcp traffic from any port going to ports less than or equal to 6000” log tcp any any -> /24 :6000 Example 2: RPC alert call alert tcp any any -> / (rpc: , *,3; msg:RPC getport (TCP);) see Snort Users Manual for more information

ECE 4112-Internetwork Security31 Defeating the IDS Encryption Insertion/evasion attacks (requires complete reassembly of packets and knowledge of end system exception handling) DoS attack (CPU, memory, bandwidth, false positives)

ECE 4112-Internetwork Security32 Signs of Intrusion Unaccountable disk utilization Unaccountable file system modification Unaccountable CPU utilization Network saturation Unknown process using sockets Abnormal network/system activity

ECE 4112-Internetwork Security33 Forensics After the attack Obtain:  Attacker(s) IP(s)  Time of attack  Victim IP, OS, and targeted service  Attacker’s activity  Attacker’s objective  Damage assessment

ECE 4112-Internetwork Security34 Forensic Guidance Photograph complete system Take detailed notes ID and secure all compromised systems Preserve evidence (UNIX)  who (who logged on)  ls (list of files)  ps (list of processes)  lsof (open file handles)  find (modified files)

ECE 4112-Internetwork Security35 Forensic Guidance System operations can lie (rootkits) Retain a provable chain of custody for evidence Make bit-image copy of hard drive and verify it Analyze