Lesson 7 Preparing for Incident Response and the Investigative Process

Lesson 7Preparing for Incident Response

and the Investigative Process

UTSA IS 6353 Incident Response

Overview

• Preparing for Incident Response

• Investigative Guidelines


Ranum on Forensics

• “The real value of intrusion detection is diagnosing what is going on…never collect more data than you could conceivably want to look at. If you don’t know what to do with the data, it doesn’t matter how much you’ve got.”

Marcus Ranum

Network Flight Recorder

Preparing for Incident Response


Identify Vital Assets

• What can damage your organization the most?• What concerns you?• Who could be a threat?• Do hackers concern you?

This step saves you time & $ later


Applicable Security Maxims

• Ignorance is Bliss Maxim: The confidence that people have in • security is inversely proportional to how much they know about it.

• Ass Sets Maxim: Most security programs focus on protecting the wrong assets.

• Takes One to Know One Maxim: The fourth most common excuse for not fixing security vulnerabilities is that “our adversaries are too stupid and/or unresourceful to figure that out.”


Preparing Systems

• Record cryptographic checksums of critical files (MD5)– Tripwire is widely accepted commercial product

• Increase or enable secure audit logging• Build up your host’s defenses• Backup critical data and store media securely• Educate users about security


Critical File Preparation

• Cryptographic checksums or Message Digest (MD)– Basically a digital signature

• MD5 creates a 128-bit checksum from a large file• System Administrator can create checksum of

critical file (use separate media) then compare against subsequent MD5 runs


Unix Auditing

Turn on system logging– /var/log/syslog– Create Central Syslog server

• run syslogd -r

– Enable Process Accounting• Tracks the command each user executes

– accton command– /usr/lib/acct/startup


Windows Auditing

• By default security auditing is not enabled• NT: Start|Programs|Administrative Tools| User

Manager– User Manager select Policies|Audit– Logs => C:\WINNT\System32\Config\*.evt

• WIN2K: Administrative Tools| Local Security Policy– Logs => C:\WINNT\System32\Config\*.evt


Other Steps

• Application Logging• Backup Critical Data

– Unix: dump, restor, cpio, tar & dd– WIN2K: Start|Programs|Accessories| System

Utilities| Backup– NT: NT Backup (NT Resources Kit)– WIN98: Start|Accessories| System Utilities| Backup


Network Preparations

• Know your network: document, document, document–hardware, software, users

• Smart topology/architecture• Use access control list (ACL) on

router


Network Preparations-contd

• Require authentication (host, network, kerberos, IPsec)

• Audit regularly (manpower intensive)• Use network time protocol (NTP) to

synchronize all events


Organizational Preparations

• Institute comprehensive policies• Institute comprehensive procedures• Develop response procedures

– Firedrills?

• Create a response toolkit• Establish an Incident Response Team• Obtain top-level management support

– Agree to ground rules/ rules of engagement

Often overlooked


Response Toolkits

• High-end processor w/lots of memory• Large IDE and SCSI drives• Backup storage: CD-RW and Tape Drives• Spare cables• Router/Hub and network interface card• Digital camera• Trusted software

ref: www.computer-forensics.com


Establish Incident Response Team

• Technical experts• Management POC• Team leader/principal investigator• Decide on mission/goal

“Critical thinking team players who enjoy hardwork and long hours”


IR Professional Organizations

Training• WWW.SANS.ORG• WWW.FOUNDSTONE.COM• WWW.CERT.ORG

Organizations• Information Sharing and

Analysis Centers (ISACs)• InfraGard• High Tech Investigation

Association• Information Systems

Security Association (ISSA)

• Forum of Incident Response and Security Teams (FIRST)

Investigative Guidelines


Investigative Guidelines

• Initial assessment• Incident notification checklist• Investigating• Formulating Response Strategy

Initial assessment not always accurate


Initial Assessment

• What probably happened?– Uncertainty regins– Each situation unique– Need to learn enough to determine course of action

• What is the best response strategy?– Does it meet pre-established goals/ROEs?– Does it have management support?– Will your team need outside help?


Incident Notification Checklist

• WWW.CERT.ORG• Collect network maps and know

architecture• Verify corporate policies

– Many actions can only be taken if appropriate policies exist


Investigating the Incident

• Prime directive: DO NO HARM• Personnel interviews• Hands-on activities• Many suspected incidents turn into non-

events• Will the investigation do more damage than

the incident itself?


Investigating the Incident-contd

• Personnel interviews– System administrators: logs– Managers: know workforce, critical data– End-users

• Taking hands-on actions– Step carefully– My contaminate “crime scene”


Formulate Response Strategy

• Declare Incident• Restore Normal Operations?

– Off-line recovery– On-line recovery

• Determine public relations play– “To spin or not to spin?”


Formulate Response Strategy-contd

• Determine probable attacker– Internal: handle internally– External: prosecute?

• Determine Type of Attack– DOS, Theft, Vandalism, Policy violation,

ongoing intrusion

• Classify victim system– Critical server/application?– # of users?


Closing Thought• “The biggest problem for 2001 was keeping

servers running MS-Windows products properly patched. We have numerous servers, and it’s constant fight to keep up with the patch level and test to confirm that the new patch doesn’t break something. This is the same problem for 2002.”

• J.G.• Do we still have this issue today? For what

OSes? Applications?Peace of mind depends on the action plan for response.


Summary

• Prepare for Incidents• Build a good team• Rehearse/Practice procedures• Perform initial assessment• Formulate response• Do No Harm

Documents

Lesson 7 Preparing for Incident Response and the Investigative Process