Chapter 9. Copyright Pearson Prentice-Hall 2010 In previous chapters, we have looked at threats, planning, and response In Chapter 9, we complete

Chapter 9

Copyright Pearson Prentice-Hall 2010

In previous chapters, we have looked at threats, planning, and response

In Chapter 9, we complete the discussion of the plan-protect-respond cycle

Response planning is necessary because defenses can never stop all attacks. Companies must respond appropriately when attacks happen or natural disasters occur

2



The Situation◦ Hurricane Katrina devastated New Orleans in

2005 Followed shortly by Hurricane Rita

◦ The U.S. Federal Emergency Management Administration (FEMA) botched the relief effort

4


Wal-Mart Is the Largest Retailer in the United States

◦ Supplied $20 million in cash

◦ Supplied 100,000 free meals

◦ 1,900 truckloads full of diapers, toothbrushes, other emergency supplies

45 trucks were rolling before the hurricane hit land

◦ Provided police and relief workers with flashlight, batteries, ammunition, protective gear, and meals

5


What Was Wal-Mart’s Process?

Wall-Mart Business Continuity Center◦ A permanent department with a small core staff

◦ Activated two days before Katrina hit

◦ Soon, 50 managers and specialists were at work in the center

6


Wall-Mart Business Continuity Center◦ Before computer network went down, sent

detailed orders to its distribution center in Mississippi

◦ Recovery merchandise for stores: bleach and mops, etc.

◦ 40 power generators to supply stores with backup power

◦ Sent loss-prevention employees to secure stores

7


Communication◦ Network communication failed

◦ Relied on telephone to contact its stores and other key constituencies

Response◦ Stores came back to business within days

◦ Engaged local law enforcement to preserve order in lines to get into stores

8


Preparation◦ Full-time director of business continuity

◦ Detailed business continuity plans

◦ Clear lines of responsibility

Multitasking◦ During all of this, were monitoring a hurricane off

Japan

9


Incidents Happen◦ Protections inevitably break down occasionally

◦ Successful attacks are called security incidents, breaches, or compromises

Incident Severity◦ False alarms

Apparent compromises are not real compromises Also called false positives Handled by the on-duty staff Waste time and may dull vigilance

10


Incident Severity◦ Minor incidents

Breaches that on-duty staff can handle Little to no management or policy issues

◦ Major incidents

Beyond the capabilities of the on-duty staff

Must convene a Computer Security Incident Response Team (CSIRT)

CSIRT needs participation beyond IT security

11


Incident Severity◦ Disasters

Fires, floods, hurricanes, major terrorist attacks Must assure business continuity

Maintaining the day-to-day operations of the firm Need a business continuity group headed by a senior

manager Core permanent staff will facilitate activities

IT disaster response is restoring IT services May be a subset of business continuity May be a stand-alone IT disaster

12


Speed and Accuracy Are of the Essence◦ Speed of response can reduce damage

Attacker will have less time to do damage

The attacker cannot burrow as deeply into the system and become very difficult to detect

Speed is also necessary in recovery

13


Speed and Accuracy Are of the Essence◦ Accuracy is equally important

Common mistake is to act on incorrect assumptions

If misdiagnose the problem or take the wrong approach, can make things much worse

Take your time quickly

14


Planning Before an Incident or Disaster◦ Decide what to do ahead of time

◦ Have time to consider matters thoroughly and without the time pressure of a crisis

◦ (During an attack, human decision-making skills degrade)

◦ Incident response is reacting to incidents according to plan

◦ Within the plan, need to have flexibility to adapt

◦ Best to adapt within a plan than to improvise completely

15


Team Members Must Rehearse the Plan◦ Rehearsals find mistakes in the plan

◦ Practice builds speed

Types of Rehearsals◦ Walkthroughs (table-top exercises)

◦ Live tests (actually doing planned actions) can find subtle problems but are expensive

16


Process for Major Incidents◦ E.g. Breach of server with sensitive customer

information

Detection, Analysis, and Escalation◦ Must detect through technology or people

Need good intrusion detection technology All employees must know how to report incidents

◦ Must analyze the incident enough to guide subsequent actions Confirm that the incident is real Determine its scope: Who is attacking; what are they

doing; how sophisticated they are, etc. Predominately done via log file analysis

17


Detection, Analysis, and Escalation◦ If deemed severe enough, escalate to a major

incident Pass to the CSIRT, the disaster response team,

or the business continuity team

18


Containment◦ Disconnection of the system from the site network

or the site network from the Internet (damaging)

Harmful, so must be done only with proper authorization

This is a business decision, not a technical decision

19


Containment◦ Black-holing the attacker (only works for a short

time) Blocking the IP address of the attacker What must be in place for this to be an

efficient/effective option? What does black-holing tell the hacker?

◦ Continue to collect data (allows harm to continue) to understand the situation Especially necessary if prosecution is desired

20


Recovery◦ Restore site from backup

But what if back-up files are compromised?

◦ Total Software installation

◦ Must leave Site more secure than before, the hackers may be back

21

If you recall….◦ Hello,During a recent security scan on our servers

it has come to our attention one of your DreamHost hosted websites have been compromised. It would appear that an unknown malicious party has modified your site's .htaccess file in order to redirect traffic destined for your website to their own site (or you have become generous and chose to re-route your site's traffic to a "sweepstakes and contests info" website.)

22

First I wanted to understand so I opened some of the infected files – with my Virus Scanner on!◦ Found I had (many files infected with)

◦ Troj/PHPShll-B Downloads more malware Downloads code from the Internet Does not allow me to edit and clean infected files So…

◦ Restore from Backup

23

I was lucky, in a sense?

My blog is not very active

So backing up from a early period did not loose any content

I deleted all the old directories◦ But kept the latest one (for investigating)

Not a good idea, I got re-hacked So I deleted again and tried to re-harden my site

24


Recovery◦ Data

Restoration from backup tapes Loses data since last trusted backup

25

After initial restore◦ Updated WordPress admin password

It wasn’t “admin”

◦ Updated WordPress to latest version

◦ I updated my Plugins


Remember I said I was hacked again

I forgot to update my themes◦ Wordpress themes are usually PHP code

◦ Determines blog look and behavior Mine was not updated So I updated it…

27

I had 69 out of date themes!!!!!!

The file hacked was .htaccess

So I found a site that had code for hardening this file:◦ WebDesignCode

◦ And changed my code

But still things were fishy so I emailed DreamHost Abuse and this is what else they did….

28

I deleted the new .htaccess file that was placed in my root directory

Though my site was available: Mydebitcredit.com

My Permalinks were broken◦ The direct link to an blog post

404 errors So DreamHost, so changed permalinks

I have an unused Domain that was a vector for some of the virus◦ Deleted two files:

◦ ./robinshermano.com/evangelin_stepped.php---------- 1 shornik pg1249160 28278 2011-08-05 13:12

◦ ./robinshermano.com/maryanna_gennie.php

29

File/Directory Permissions◦ When we've seen files that match that naming

convention and size signature arise over the last couple of months, it is typically due to the folder that it resides in having insecure 777 permission settings that allow for the global writing of files by any user. This means that if another user on the shared server is hacked, the attackers, if they scan for folders with this insecure setting can then place files in the folder , such as the above listed backdoor shell which they later hit via HTTP to inject a base64 encoded payload into your files.

30

31

32

33


Recovery◦ Software

Total software reinstallation of operating system and applications may be necessary for the system to be trustable

Manual reinstallation of software Need installation media and product activation keys Must have good configuration documentation before the

incident

Reinstallation from a disk image Can greatly reduce time and effort Requires a recent disk image

34


Apology◦ Acknowledge responsibility and harm without

evasion or weasel words

◦ Explain potential inconvenience and harm in detail

◦ Explain what actions will be taken to compensate victims, if any

35


Punishment◦ Punishing employees usually is fairly easy

Most employees are at-will employees

Companies usually have wide discretion in firing at-will employees

This varies internationally

Union agreements may limit sanctions or at least require more detailed processes

36


Punishment◦ The decision to pursue criminal prosecution

Must consider cost and effort

Must consider probable success if pursue (often attackers are minors or foreign nationals)

Loss of reputation because the incident becomes public

37


Punishment◦ Collecting and managing evidence

Forensics: Courts have strict rules for admitting evidence in court

Call the authorities and a forensics expert for help

38


Punishment◦ Collecting and managing evidence

Protecting evidence Pull the plug on a server if possible This is a business decision, not an IT decision

Document the chain of custody Who held the evidence at all times What they did to protect it Document the chain of custody

39


Postmortem Evaluation◦ What should we do differently next time?

◦ I’ve set up my them to update automatically and only have 1 theme to keep tack of.

◦ I still need to check for updates of WordPress and Plugins routinely

40


Organization of the CSIRT◦ Should be led by a senior manager

◦ Should have members from affected line operations

◦ The IT security staff may manage the CSIRT’s operation on a day-to-day basis

◦ Might need to communicate with the media; only do so via public relations

◦ The corporate legal counsel must be involved to address legal issues

◦ Human resources is necessary, especially if there are to be sanctions against employees

41

Carnegie Mellon Computer Emergency Response Team (CERT)◦ XNET



Dimension Criminal Law Civil LawDeals with Violations of criminal

statutesInterpretations of rights and duties that companies or individuals have relative to each other

Penalties Jail time and fines Monetary penalties and orders to parties to take or not take certain actions

Cases brought by Prosecutors Plaintiff is one of the two parties

Criterion for verdict Beyond a reasonable doubt

Preponderance of the evidence (usually)

Requires mens rea (guilty mind)

Usually Rarely, although may affect the imposed penalty

Applicable to IT security Yes. To prosecute attackers and to avoid breaking the law

Yes. To avoid or minimize civil trials and judgments


Cyberlaw◦ Cyberlaw is any law dealing with information

technology

Jurisdictions◦ Areas of responsibility within which government

bodies can make and enforce law but beyond which they cannot

44


The United States Federal Judicial System◦ U.S. District Courts

94 in the United States

Decisions in trials are only binding on the litigants

45


The United States Federal Judicial System◦ U.S. Circuit Courts of Appeal

13 in the United States

Do not conduct trials

Review district court decisions

Decisions are precedents only for the district courts under the circuit court of appeals making a decision

46


The United States Federal Judicial System◦ U.S. Supreme Court

Final arbiter of U.S. federal law

Only hears about 100 cases per year

Usually only reviews cases that involve conflicts between appellate court precedents or important constitutional issues

47


U.S. State and Local Law◦ In the United States, many powers are reserved

for the states

◦ This typically includes the prosecution of crimes taking place within a state or that do not affect interstate commerce

◦ For most cybercrimes committed within a state, state law applies

◦ State cybercrime laws vary widely

◦ Local police usually investigate crimes under both local and state laws

48


International Law◦ Differences are wide and rapidly changing

(generally improving)

◦ Important to multinational firms

◦ Also important to purely domestic firms Suppliers and buyers may be in other countries Attackers may be in other countries

◦ Several treaties exist to harmonize laws and facilitate cross-border prosecution Generally immature

49


Admissibility of Evidence◦ Unreliable evidence may be kept from juries

◦ Belief that juries cannot evaluate unreliable evidence properly

◦ Example: hearsay evidence

Federal Rules of Civil Procedure◦ Guide U.S. courts

◦ Now have strong rules for evaluating the admissibility of electronic evidence

50


Computer Forensics Experts◦ Professionals trained to collect and evaluate

computer evidence in ways that are likely to be admissible in court

◦ Meet with them before there is a need because the initial moments of an intrusion require correct action

51


Expert Witnesses◦ Normally, witnesses can only testify regarding

facts, not interpretations

◦ Expert witnesses may interpret facts to make them comprehensible to the jury in situations where juries are likely to have a difficult time evaluating the evidence themselves

52


18 U.S.C § 1030◦ United States Code Title 18, Part I (Crimes)

Section 1030

◦ Actions prohibited Hacking Malware Denial of service

53


18 U.S.C § 1030◦ Protected computers

Applicability is limited to protected computers Include “government computers, financial

institution computers, and any computer which is used in interstate or foreign commerce or communications”

◦ Often require damage threshold for prosecution The FBI may require even higher damages to

prosecute

54


18 U.S.C § 2511◦ Prohibits the interception of electronic messages,

both en route and after the message is received and stored

◦ Allows e-mail service providers to read the content of mail A company can read employee mail if it owns

the mail system

55


Other Federal Laws◦ Many traditional federal criminal laws may apply

in individual cases

◦ For example, fraud, extortion, and the theft of trade secrets

◦ These laws often have far harsher consequences than cybercrime laws

56


Event logging for suspicious events

Sometimes, send alarms

A detective control, not a preventative or restorative control

57


Management:

Configuration, Tuning, etc.

Actions:

Generate Alarms

Generate Log Summary Reports

Support Interactive Manual Log Analysis

Automated Analysis:

Attack Signatures versus Anomaly Detection

Event Logging:

Individual Events are Time-Stamped

Log is Flat File of Events

(Sometimes) Data Aggregation from Multiple IDSs

Logging◦ Captures discrete events time-stamped

◦ Stored in a sequential file

Automated Analysis◦ Attack Signatures (see my Hack)

◦ Anomaly Detection Deviations from past activity

Actions◦ Alarm

◦ Log Summary Reports should be reviewed

◦ Support Interactive Log Analysis Tools


Multiple IDS allow a better overview of attack Agents

◦ Each device collecting data/event

Manger program◦ Integrates log files from all sources

◦ Batch transfers Least expensive

Hacker disables event logging, if done between batches hack may go undetected

Real-Tim More expensive Doesn’t suffer from hacking



1.Manager

2.IntegratedLog File

4.Agent:

NetworkIDS

4.Agent:

Network IDS

3.Agent:HostIDS

Switch

Router Firewall

IDS Vendor

5.Encrypted

Communication

5.Encrypted

Communication

4.Agent:

NetworkIDS


Network IDSs (NIDSs)◦ Stand-alone device or built into a switch or router

◦ NIDSs see and can filter all packets passing through them

◦ Switch or router NIDSs can collect data on all ports

◦ A NIDS collects data for only its portion of the network Blind spots in network where no NIDS data is

collected

◦ Cannot filter encrypted packets

62


Host IDSs (HIDSs)◦ Attractions

Provide highly detailed information for the specific host

◦ Weaknesses of Host IDSs Limited Viewpoint; Only one host Host IDSs can be attacked and disabled

63


Host IDSs (HIDSs)◦ Operating System Monitors

Collects data on operating system events Multiple failed logins Creating new accounts Adding new executables (programs—may be

attack programs)

64


Host IDSs (HIDSs)◦ Operating System Monitors

Modifying executables (installing Trojan horses does this)

Adding registry keys (changes how system works)

Changing or deleting system logs and audit files Changing system audit policies User accessing critical system files User accessing unusual files Changing the OS monitor itself

65


Log Files◦ Flat files of time-stamped events

◦ Individual logs for single NIDs or HIDs

◦ Integrated logs Aggregation of event logs from multiple IDS

agents (Figure 9-12) Difficult to create because of format

incompatibilities Time synchronization of IDS event logs is crucial

(Network Time Protocol)

66


Event Correlation (Figure 9-15)◦ Suspicious patterns in a series of events across

multiple devices

◦ Difficult because the relevant events exist in much larger event streams that are logged

◦ Usually requires many analysis of the integrated log file data

67


Sample Log File(many irrelevant log entries not shown)

1. 8:45:05:47. Packet from 1.15.3.6 to 60.3.4.5 (NIDS log entry)

2. 8:45:07:49. Host 60.3.4.5. Failed login attempt for account Lee (Host 60.3.4.5 log entry)

3. 8:45:07:50. Packet from 60.3.4.5 to 1.15.3.6 (NIDS) 4. 8:45:50:15. Packet from 1.15.3.6 to 60.3.4.5 (NIDS) 5. 8:45:50:18. Host 60.3.4.5. Failed login attempt for

account Lee (HIDS) 6. 8:45:50:19. Packet from 60.3.4.5 to 1.15.3.6 (NIDS) 7. 8:49:07:44. Packet from 1.15.3.6 to 60.3.4.5 (NIDS) 8. 8:49:07:47. Host 60.3.4.5. Successful login attempt

for account Lee (HIDS) 9. 8:49:07:48. Packet from 60.3.4.5 to 1.15.3.6 (NIDS)

68


Sample Log File 10. 8:56:12:30. Packet from 60.3.4.5 to 123.28.5.210.

TFTP request (NIDS)

11. 8:56:28:07. Series of packets from 123.28.5.210 and 60.3.4.5. TFTP response (NIDS)

12. No more host log entries

◦ (The log would not say this; it would merely stop sending events)

69


Sample Log File

(many irrelevant log entries not shown)

13. 9:03.17:33. Series of packets between 60.3.4.5 and 1.17.8.40. SMTP (NIDS)




17. 9:20:12:05. Packet from 60.3.4.5 to 60.0.1.1. TCP SYN=1, Destination Port 80 (NIDS)

18. 9:20:12:07: Packet from 60.0.1.1 to 60.3.4.5. TCP RST=1, Source Port 80 (NIDS)

19. 9:20:12:08. Packet from 60.3.4.5 to 60.0.1.2. TCP SYN=1, Destination Port 80 (NIDS)

20. 9:20:12:11 Packet from 60.3.4.5 to 60.0.1.3. TCP SYN=1, Destination Port 80 (NIDS)

21. 9:20:12:12. Packet from 60.0.1.3 to 60.3.4.5. TCP SYN=1; ACK=1, Source Port 80 (NIDS)

70


Tuning for Precision◦ Too many false positives

False alarms Can overwhelm administrators, dull vigilance

◦ False negatives allow attacks to proceed unseen

71


Tuning for Precision◦ Tuning for false positives turns off unnecessary

rules, reduces alarm levels of unlikely rules

For instance, alarms for attacks against Solaris operating systems can be deleted if a firm has no Sun Microsystems servers

Tuning requires a great deal of expensive labor

Even after tuning, most alerts will be false positives

72


Updates◦ Program, attack signatures must be updated

frequently

Processing Performance◦ If processing speed cannot keep up with network

traffic, some packets will not be examined

◦ This can make some IDSs useless during attacks that increase the traffic load

73


Storage◦ There will be limited disk storage for log files

◦ When log files reach storage limits, they must be archived

◦ Event correlation is difficult across multiple backup tapes

◦ Adding more disk capacity reduces the problem but never eliminates it

74


Business Continuity Planning◦ A business continuity plan specifies how a

company plans to restore or maintain core business operations when disasters occur

◦ IT Disaster response is restoring IT services

75


Principles of Business Continuity Management◦ Protect people first

Evacuation plans and drills Never allow staff members back into unsafe

environments Must have a systematic way to account for all

employees and notify loved ones Counseling afterwards

76


Principles of Business Continuity Management◦ People have reduced capacity in decision making

during a crisis Planning and rehearsal are critical

◦ Avoid rigidity Unexpected situations will arise Communication will break down and information

will be unreliable Decision makers must have the flexibility to act

77


Principles of Business Continuity Management◦ Communication

Try to compensate for inevitable breakdowns Have a backup communication system Communicate constantly to keep everybody “in

the loop”

78


Business Process Analysis◦ Identification of business processes and their

interrelationships

◦ Prioritization of business processes Downtime tolerance (in the extreme, mean time

to belly-up) Importance to the firm Required by higher-importance processes

◦ Resource needs (must be shifted during crises) Cannot restore all business processes

immediately

79


Testing the Plan◦ Difficult because of the scope of disasters

◦ Difficult because of the number of people involved

80


Updating the Plan◦ Must be updated frequently

◦ Business conditions change and businesses reorganize constantly

◦ People who must execute the plan also change jobs constantly

◦ Telephone numbers and other contact information must be updated far more frequently than the plan as a whole

◦ Should have a small permanent staff

81


Business Continuity:Keeping the entire firm operatingor restoring the firm to operation

IT Disaster Response:Keeping IT resources operatingor restoring them to operation


IT Disaster Recovery◦ IT disaster recovery looks specifically at the

technical aspects of how a company can get its IT back into operation using backup facilities

◦ A subset of business continuity or for disasters the only affect IT

◦ All decisions are business decisions and should not be made by mere IT or IT security staffs

83


Types of Backup Facilities◦ Hot sites

Ready to run (power, HVAC, computers): Just add data

Considerations: Rapid readiness at high cost

Must be careful to have the software at the hot site up-to-date in terms of configuration

84


Types of Backup Facilities◦ Cold sites

Building facilities, power, HVAC, communication to outside world only

No computer equipment

Less expensive but usually take too long to get operating

85


Types of Backup Facilities◦ Site sharing

Site sharing among a firm’s sites (problem of equipment compatibility and data synchronization)

Continuous data protection needed to allow rapid recovery

86


Office Computers◦ Hold much of a corporation’s data and analysis

capability

◦ Will need new computers if old computers are destroyed or unavailable Will need new software Well-synchronized data backup is critical

◦ People will need a place to work

87


Restoration of Data and Programs◦ Restoration from backup tapes: Need backup

tapes at the remote recovery site

◦ May be impossible during a disaster

Testing the IT Disaster Recovery Plan◦ Difficult and expensive

◦ Necessary

88

Or, as we say in Hawaii, “All pau”

89

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic,

mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America.

Copyright © 2010 Pearson Education, Inc. Copyright © 2010 Pearson Education, Inc. Publishing as Prentice HallPublishing as Prentice Hall

Documents

Chapter 9. Copyright Pearson Prentice-Hall 2010 In previous chapters, we have looked at threats, planning, and response In Chapter 9, we complete