CERT

CARNEGIE MELLON UNIVERSITY

An Analysis Of Security Incidents On The Internet

1989 - 1995

A dissertation submitted to the graduate school

in partial fulfillment of the requirements for the degree of

Doctor of Philosophy

in

Engineering and Public Policy

by

John D. Howard

Pittsburgh, Pennsylvania 15213 USA

April 7, 1997


© Copyright by John D. Howard, 1997. All rights reserved.



Abstract

This research analyzed trends in Internet security through an investigation of 4,299 security-related incidents on the Internet reported to the CERT® Coordination Center (CERT®/CC) from 1989 to 1995. Prior to this research, our knowledge of security problems on the Internet was limited and primarily anecdotal. This information could not be effectively used to determine what government policies and programs should be, or to determine the effectiveness of current policies and programs. This research accomplished the following: 1) development of a taxonomy for the classification of Internet attacks and incidents, 2) organization, classification, and analysis of incident records available at the CERT®/CC, and 3) development of recommendations to improve Internet security, and to gather and distribute information about Internet security.

With the exception of denial-of-service attacks, security incidents were generally found to be decreasing relative to the size of the Internet. The probability of any severe incident not being reported to the CERT®/CC was estimated to be between 0% and 4%. The probability that an incident would be reported if it was above average in terms of duration and number of sites, was around 1 out of 2.6. Estimates based on this research indicated that a typical Internet domain was involved in no more than around one incident per year, and a typical Internet host in around one incident every 45 years.

The taxonomy of computer and network attacks developed for this research was used to present a summary of the relative frequency of various methods of operation and corrective actions. This was followed by an analysis of three subgroups: 1) a case study of one site that reported all incidents, 2) 22 incidents that were identified by various measures as being the most severe in the records, and 3) denial-of-service incidents. Data from all incidents and these three subgroups were used to estimate the total Internet incident activity during the period of the research. This was followed by a critical evaluation of the utility of the taxonomy developed for this research. The analysis concludes with recommendations for Internet users, Internet suppliers, response teams, and the U.S. government.

Keywords: Internet, computer, network, computer security, hacker, public policy, taxonomy, Unix, CERT®

Acknowledgments

My thanks goes first and foremost to my family, Diane Howard, and our children, Jessica, Rachel, Luke and Nathan. They gave me their support during my studies at Carnegie Mellon University, while enduring poverty and neglect. I am indebted to them for their understanding and their encouragement.

I am indebted also to my dissertation committee. Dr. Paul S. Fischbeck was my advisor throughout my studies at CMU, and he was chairman of the committee. Thanks to him for his insight, instruction, support and patience. He has high standing among that rare breed of professors who always place their students as their first priority. Thanks also to Dr. Thomas A. Longstaff of the CERT®/CC. He introduced me to the CERT®/CC records, was instrumental in providing me a place to work, and helped me understand the records and the operation of his organization. He also provided me valuable insight which I was able to apply to the research. Thanks also to Dr. M. Granger Morgan, Department Head, Engineering and Public Policy (EPP). He supported me when I needed it, and was always a learned instructor. I also appreciate the help from Dr. Alex Hills, head of CMU Computing Services. Thanks particularly to him for teaching me about telecommunications policy. And much thanks to the entire committee for their timely insights, particularly the suggestions each of them made for adding more conclusions and recommendations. With a few questions to me, they were able to allow me to see that my research had broader and more important implications than I had initially realized.

Many thanks also to the other members of the CERT®/CC team who cheerfully responded to my many needs during the research, particularly Katherine Fithen, who acted as a liaison with Site A and carefully read the completed dissertation for accuracy and to check that all the material could be released, and Howard Lipson, who helped me with many technical questions and with the procedures and software for safeguarding the records. Thanks also to Richard Pethia, Barbara Fraser, Moira West-Brown, James Ellis, Ed DeHart, Derek Simmel, and James Stevens.

Thanks to the Engineering and Public Policy Department for their support, both intellectually and financially. Dr. Indira Nair, in particular, helped me throughout the EPP program. Thanks to her for her encouragement in applying to EPP, her advice and insight, and for reminding me of the importance of ethics in our professional and personal lives. Thanks also to my other instructors, Dr. Benoit Morel, Dr. Michael Meyer, Dr. Mitchell Small, Dr. Mark Fichman, and Dr. Jon Peha, and the EPP staff, particularly Vicki Massimino, Patti Steranchak and Denise Murrin-Macey.

During the 1996-97 academic year, I was Visiting Professor in the Computer Science Department at the US Air Force Academy. Thanks to the members of the department for their encouragement and understanding while I completed the dissertation, and particularly to Colonel Samuel Grier, Department Head and Permanent Professor, who allowed me time for the research. Thanks also to Major Rick Mraz for his encouragement, help and insight while I struggled to conceptualize the taxonomy, to Captain Jonathan Robinson for his help on the statistics, and Lieutenant Colonel Greg White for his understanding of Information Warfare.

And finally, my warmest thanks to my fellow traveler through CMU, my friend and confidant, Dr. Karen Jenni. She provided me support and sanity that was much needed, and much relied on.

Table of Contents - Summary

Abstract

Acknowledgments

Table of Contents - Summary

Table of Contents

List of Figures

List of Tables

Chapter 1. Introduction

Chapter 2. Internet Characteristics

Chapter 3. CERT®/CC History and Policies

Chapter 4. CERT®/CC Records

Chapter 5. A Formal Definition of Computer Security

Chapter 6. A Taxonomy of Computer and Network Attacks

Chapter 7. Classification of Internet Incidents and Internet Activity

Chapter 8. Methods of Operation and Corrective Actions

Chapter 9. Case Study - Site A

Chapter 10. Severe Incidents

Chapter 11. Denial-of-Service Incidents

Chapter 12. Estimates of Total Internet Incident Activity

Chapter 13. The Utility of the Taxonomy of Computer and Network Attacks

Chapter 14. Policy Implications and Recommendations

Chapter 15. Future Research

Chapter 16. Conclusions and Recommendations

References

Appendix A. Summary of Methods of Operation

Appendix B. Summary of Corrective Actions

Glossary



Table of Contents

Abstract

Acknowledgments

Table of Contents - Summary

Table of Contents

List of Figures

List of Tables

Chapter 1. Introduction

1.1. A Scary Place?

1.2. Contributions of this Research

1.3. Recommended Actions

1.4. Why Comprehensive Information Was Not Available on Internet Incidents

1.5. Overview

Chapter 2. Internet Characteristics

2.1. Description and Origins of the Internet

2.2. Internet Hosts and Domains

2.2.1. IP addressess

2.2.2. Domain Names

2.2.3. Domains

2.3. Domain Name System (DNS) Terminology

2.4. Site Names

2.5. The Internet Domain Survey

2.6. Estimated Growth of the Internet

2.7. Summary of Internet Characteristics

Chapter 3. CERT®/CC History and Policies

3.1. Origins of the CERT®/CC

3.2. CERT®/CC Purpose

3.3. Operating Procedures and Policies

3.4. Other Incident Response and Security Teams

3.5. Summary of CERT®/CC History and Policies

Chapter 4. CERT®/CC Records

4.1. CERT®/CC Incident Response

4.1.1. Early, Informal Period -- November, 1988 to January, 1992

4.1.2. Transition Period -- January, 1992 to September, 1993

4.1.3. Formal Period -- September, 1993 to December, 1995

4.2. CERT®/CC Record Characteristics and Methods of Analysis

4.2.1. Early Period Records -- November, 1988 to May, 1992

4.2.2. Later Period Records -- May, 1992 to December, 1995

4.3. Data Extraction

4.4. Summary of CERT®/CC Records

Chapter 5. A Formal Definition of Computer Security

5.1. Simple Computer Security Definitions

5.2. Narrowing the Definition of Computer Security

5.3. Toward a More Formal Definition

5.3.1. What resources are we trying to protect?

5.3.2. Against what?

5.4. A Formal Definition of Computer Security

Chapter 6. A Taxonomy of Computer and Network Attacks

6.1. Characteristics of Satisfactory Taxonomies

6.2. Toward a Taxonomy of Computer and Network Attacks

6.3. Current Computer and Network Security Taxonomies

6.3.1. Lists of Terms

6.3.2. Lists of Categories

6.3.3. Results Categories

6.3.4. Empirical Lists

6.3.5. Matrices

6.3.6. A Process-Based Taxonomy

6.4. A Taxonomy of Computer and Network Attacks

6.4.1. Attackers and Their Objectives

6.4.2. Access

6.4.3. Results

6.4.4. Tools

6.4.4.1 User Command

6.4.4.2 Script or Program

6.4.4.3 Autonomous Agent

6.4.4.4 Toolkit

6.4.4.5 Distributed Tool

6.4.4.6 Data Tap

6.4.5. The Complete Taxonomy of Computer and Network Attacks

6.5. Summary of the Taxonomy of Computer and Network Attacks

Chapter 7. Classification of Internet Incidents and Internet Activity

7.1. Number of CERT®/CC Incidents

7.2. Classification of Incidents

7.2.1. False Alarms

7.2.2. Unauthorized Access Incidents

7.2.3. Unauthorized Use Incidents

7.2.4. Inadequacies of this Classification

7.3. Alternate Measures of Severity

7.4. Sites per Day Recorded in the CERT®/CC Incidents

7.5. Summary of the Classification of Internet Incidents and Internet Activity

Chapter 8. Methods of Operation and Corrective Actions

8.1. Methods of Operation

8.1.1. Attackers

8.1.2. Tools

8.1.3. Access

8.1.3.1 Password Vulnerabilities

8.1.3.2 SMTP

8.1.3.3 Mail

8.1.3.4 Trusted hosts

8.1.3.5 Configuration

8.1.3.6 TFTP

8.1.3.7 NIS

8.1.3.8 FTP

8.1.3.9 NFS

8.1.3.10 Other vulnerabilities

8.1.3.11. Types of Accounts

8.1.4. Results

8.1.5. Objectives

8.1.6. Summary of Methods of Operation

8.2. Corrective Actions

8.2.1. Internal Actions

8.2.2. External Actions

8.3. Some Things the CERT®/CC Incidents Do Not Include

8.4. Summary of Methods of Operation and Corrective Actions

Chapter 9. Case Study - Site A

9.1. Description of Site A

9.2. Site A Reporting Criteria

9.3. Classification of Site A Incidents

9.3.1. False Alarms

9.3.2. Unauthorized Access Incidents at Site A

9.3.3. Unauthorized Use Incidents at Site A

9.4. Sites per Day

9.5. Summary of Case Study - Site A

Chapter 10. Severe Incidents

10.1. Selection of the Severe Incidents

10.2. Description of the Severe Incidents Chosen

10.2.1. Incident #1 - Dutch Hackers

10.2.2. Incident #9 - Danish Hackers

10.2.3. Incidents #2, 3, 4, and 8 - Other Command Line Incidents

10.2.4. Incident #5 - FTP Abuse and Software Piracy

10.2.5. Incident #7 - TFTP Attacks

10.2.6. Incidents #6, 10, 11, 12, 13, 14, 17 - Sniffer Attacks

10.2.7. Incident #15, 18, 19, 21, 22 - Toolkit and Sniffer Attacks

10.2.8. Incident #16 - Toolkit, Sniffer and IRC

10.2.9. Incident #20 - IP Spoofing

10.3. Summary of Severe

Chapter 11. Denial-of-Service Incidents

11.1. Denial-of-service Definition and Types

11.1.1 Destruction

11.1.2 Process Degradation

11.1.3 Storage Degradation

11.1.4. Shutdowns

11.2. History of Internet Denial-of-Service Attacks

11.2.1. Numbers of Attacks

11.2.2. Methods of Attack

11.2.3. Additional Denial-of-service Attack Characteristics

11.3. Summary of Denial-of-Service Incidents

Chapter 12. Estimates of Total Internet Incident Activity

12.1. Relationship of Attacks, Incidents and Total Activity

12.2. Estimates of Total Internet Attack Activity

12.2.1. Monitoring Sites For Attack Activity

12.2.2. Reports of Attack Activity From Representative Sites

12.2.3. Vulnerability Studies

12.2.3.1. DISA Vulnerability Studies

12.2.3.2. AFIWC Security Posture Studies 175

12.3. Estimates of Total Internet Incident Activity

12.3.1. Monitoring Sites For Incident Activity

12.3.2. Reports of Incident Activity From Representative Sites

12.3.3. Estimates of Attack Reporting Rate and Attacks per Incident

12.3.3.1. Estimates of Attack Reporting Rate

12.3.3.2. Estimates of Attacks per Incident Using All CERT®/CC Incident

12.3.3.3. Estimates of Attacks per Incident Using CERT®/CC Incidents by Type

12.3.4. Summary of Incident Estimates

12.4. Severe and Above Average Incidents

12.5. Estimated Number of Internet Denial-of-service Incidents

12.6. Summary of the Estimates of Total Internet Incident Activity

Chapter 13. The Utility of the Taxonomy of Computer and Network Attacks

13.1. Review of the Characteristics of Satisfactory Taxonomies

13.2. Evaluation of the taxonomy relative to the taxonomy criteria

13.2.1. Categories that are Mutually Exclusive

13.2.2. Categories that are Exhaustive

13.2.3. Categories that are Unambiguous

13.2.4. Categories that are Repeatable

13.2.5. Categories that are Accepted

13.2.6. Categories that are Useful

13.3. Classifications of Incidents

13.3.1 Classifications at the CERT®/CC during the period of research

13.3.2. Classification of Incidents for this Research

13.3.3. Recommended Process for Classifying Incidents

13.3.3.1. Determining Incident Scope

13.3.3.2. Determining Incident Characteristics

13.3.3.3. Classification of Incidents

13.4. Summary of the Utility of the Taxonomy of Computer and Network Attacks

Chapter 14. Policy Implications and Recommendations

14.1. General Implications of This Research

14.2. Implications for Internet Users

14.2.1. Basic Precautions All Users Should Take to Protect Files

14.2.2. Advanced Precautions to Protect Files

14.2.3. Precautions to Protect Data in Transit

14.2.4. Additional Considerations for Commercial Internet Users

14.2.5. Summary of the Implications for Internet Users

14.3. Implications for Internet Suppliers

14.3.1. Password Problems

14.3.2. Shipping Software in an Insecure State

14.3.3. Additional Actions Suppliers Should Take

14.3.4. Summary of Implications for Suppliers

14.4. Implications for the Government

14.4.1. The Government's Role in Providing Information

14.4.2. Government Information Policies and the Computer Security Market

14.4.3. Funding of Incident Response Supported by This Research

14.4.4. Other Government Policies Supported by This Research

14.5. Implications for Response Teams

14.5.1. Objectives of Incident Response

14.5.2. Possible Alternative Courses of Action

14.5.2.1. Disclosure of Site Names

14.5.2.1.1. Alternative 1.1 - Full Disclosure of Site Names

14.5.2.1.2. Alternative 1.2 - Partial Disclosure of Site Names

14.5.2.1.3. Alternative 1.3 - Delayed Disclosure of Site Names

14.5.2.1.4. Alternative 1.4 - No Disclosure of Site Names

14.5.2.1.5. Recommended Alternative for the Disclosure of Site Names

14.5.2.2. Disclosure of Incident Activity

14.5.2.2.1. Alternative 2.1 - Disclosure of CERT® Summaries

14.5.2.2.2. Alternative 2.2 - Creation and Disclosure of Incident Files

14.5.2.2.3. Alternative 2.3 - Development and Disclosure of Incident Data based on Incident Summaries

14.5.2.2.4. Alternative 2.4 - Development and Disclosure of Incident Data based on a Taxonomy

14.5.2.2.5. Alternative 2.5 - Limited Disclosure of Incident Activity

14.5.2.2.6. Recommended Alternative for the Disclosure of Incident Activity

14.5.2.3. Disclosure of Vulnerabilities

14.5.3. Other Implications for Response Teams

14.6. Implications for the CERT®/

14.7. Summary of Policy Implications and Recommendations

Chapter 15. Future Research

Chapter 16. Conclusions and Recommendations

16.1. Contributions of this Research

16.2. A Taxonomy of Computer and Network Attacks

16.3. Classification of Internet Incidents and Internet Activity

16.4. Tools and Vulnerabilities

16.5. Severe Incidents

16.6. Denial-of-Service Incidents

16.7. Estimates of Total Internet Incident

16.8. Policy Implications and Recommendations

16.9. Future Research

References

Appendix A. Summary of Methods of Operation

Appendix B. Summary of Corrective Actions

Glossary

List of Figures

Chapter 2

Figure 2.1. Typical Internet Domain Name Tree

Figure 2.2. Growth in Internet Hosts

Figure 2.3. Projected Internet Growth

Figure 2.4. Growth of Top-Level Domains with Predominantly U.S. Hosts

Figure 2.5. Growth of Top-Level Domains with Predominantly U.S. Hosts

Figure 2.6. Top-Level Domains as a Percentage of the Internet

Figure 2.7. Growth in DNS domains

Figure 2.8. Trends in Internet Hosts per DNS domain

Figure 2.9. Growth of the World Wide Web

Chapter 6

Figure 6.1. Example Two-Dimensional Attack Matrix

Figure 6.2. Security flaw taxonomy: Flaws by Genesis

Figure 6.3. Security Attacks

Figure 6.4. Operational Sequence of Computer and Network Attack

Figure 6.5. Attackers and their Primary

Figure 6.6. Access for Attack

Figure 6.7. Results of Attack

Figure 6.8. Tools of Attack

Figure 6.9. Complete Computer and Network Attack Taxonomy

Chapter 7

Figure 7.1. CERT®/CC Incidents per Year

Figure 7.2. CERT®/CC Incidents by Month, 1989 - 1995

Figure 7.3. CERT®/CC Incidents and False Alarms per Year

Figure 7.4. False Alarms as a Percentage of CERT®/CC Incidents

Figure 7.5. Access for

Figure 7.6. CERT®/CC Access Incidents by Month Averaged Over Quarters

Figure 7.7. CERT®/CC Access Incidents per 100,000 domains by Month Averaged Over Quarters

Figure 7.8. CERT®/CC Access Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 7.9. CERT®/CC Successful Access Incidents by Month Averaged Over Quarters

Figure 7.10. CERT®/CC Successful Access Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 7.11. CERT®/CC Total Unauthorized Use Incidents by Month Averaged Over Quarters

Figure 7.12. CERT®/CC Abuse Incidents by Month Averaged Over Quarters

Figure 7.13. CERT®/CC Total Unauthorized Use Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 7.14. CERT®/CC Abuse Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 7.15. CERT®/CC Denial-of-service Incidents by Month Averaged Over Quarters

Figure 7.16. CERT®/CC Denial-of-service Incidents per 10,000,000 Hosts by Month Averaged Over

Figure 7.17. CERT®/CC Spoofing Incidents by Month Averaged Over Quarters

Figure 7.18. CERT®/CC Spoofing Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 7.19. CERT®/CC Sites per Day - All Incidents

Figure 7.20. CERT®/CC Sites per Day - All Incidents, Averaged Over Months

Figure 7.21. CERT®/CC Sites per Day - All Incidents, Averaged Over Quarters

Figure 7.22. CERT®/CC Sites per Day - Root and Account Break-ins, Averaged Over Months

Figure 7.23. CERT®/CC Sites per Day - Root and Account Break-ins, Averaged Over Quarters

Figure 7.24. CERT®/CC Sites per Day per 10,000,000 Hosts - All Incidents, Averaged Over Quarters

Figure 7.25. CERT®/CC Sites per Day per 10,000,000 Hosts - Root and Account Break-ins, Averaged Over Quarters

Chapter 8

Figure 8.1. Range and Mean Incident Reporting Dates for Methods of Operation - Attackers

Figure 8.2. Range and Mean Incident Reporting Dates for Methods of Operation - Tools

Figure 8.3. Range and Mean Incident Reporting Dates for Methods of Operation - Access - Part 1

Figure 8.4. Range and Mean Incident Reporting Dates for Methods of Operation - Access - Part 2

Figure 8.5. Range and Mean Incident Reporting Dates for Methods of Operation - Access - Part 3

Figure 8.6. Range and Mean Incident Reporting Dates for Methods of Operation - Access - Part 4

Figure 8.7. Range and Mean Incident Start for Methods of Operation - Access - Type of Account

Figure 8.8. Range and Mean Incident Reporting Dates for Methods of Operation - Results

Figure 8.9. Range and Mean Incident Reporting Dates for Methods of Operation - Objectives

Figure 8.10. Range and Mean Incident Reporting Dates for Corrective Actions

Chapter 9

Figure 9.1. Site A Incidents and False Alarms per Year

Figure 9.2. False Alarms as a Percentage of Site A Incidents

Figure 9.3. Site A Incidents per Month (with and without false alarms)

Figure 9.4. Site A Access Incidents by Month Averaged Over Quarters

Figure 9.5. Site A Access Incidents per 100,000 domains by Month Averaged Over Quarters

Figure 9.6. Site A Access Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.7. Site A Successful Access Incidents by Month Averaged Over Quarters

Figure 9.8. Site A Successful Access Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.9. Site A Total Unauthorized Use Incidents by Month Averaged Over Quarters

Figure 9.10. Site A Total Unauthorized Use Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.11. Site A Abuse Incidents by Month Averaged Over Quarters

Figure 9.12. Site A Abuse Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.13. Site A Denial-of-service Incidents by Month Averaged Over Quarters

Figure 9.14. Site A Denial-of-service Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.15. Site A Spoofing Incidents by Month Averaged Over Quarters

Figure 9.16. Site A Spoofing Incidents per 10,000,000 Hosts by Month Averaged Over Quarters

Figure 9.17. Site A Sites per Day - All Incidents

Figure 9.18. Site A Sites per Day - All Incidents, Averaged Over Months

Figure 9.19. Site A Sites per Day - All Incidents, Averaged Over Quarters

Figure 9.20. Site A Sites per Day per 10,000,000 Hosts - All Incidents, Averaged Over Quarters

Figure 9.21. Site A Sites per Day - Root and Account Break-ins, Averaged Over Months

Figure 9.22. Site A Sites per Day - Root and Account Break-ins, Averaged Over Quarters

Figure 9.23. Site A Sites per Day per 10,000,000 Hosts - Root and Account Break-ins, Averaged Over Quarters

Chapter 10

Figure 10.1. Number of Sites versus Number of Incidents

Figure 10.2. Number of Sites versus Number of Incidents (Less than 200 sites and less than 500 Incidents)

Figure 10.3. Incident Duration versus Number of Incidents

Figure 10.4. Incident Duration versus Number of Incidents (200 or Less Days and less than 1000 Incidents)

Figure 10.5. Number of Messages versus Number of Incidents

Figure 10.6. Number of Messages versus Number of Incidents (Less than 200 messages and less than 500 Incidents)

Figure 10.7. Distribution of Root Break-in Incidents With 79 Days Duration, 62 Sites, 87 Messages

Figure 10.8. Sites per Day versus Duration for 22 "Severe" Incidents

Chapter 11

Figure 11.1. Denial-of-Service Attack Methods

Figure 11.2. Internet Protocol Layering Compared to Network Process Categories

Figure 11.3. Sites per Day Involved in Denial-of-service Attacks, Averaged Over Each Quarter, as Recorded in CERT®/CC Records

Figure 11.4. Sites per Day Involved in Denial-of-service Attacks, per 100,000 Internet Domains Averaged Over Each Quarter, as Recorded in CERT®/CC Records

Figure 11.5. Sites per Day Involved in Denial-of-service Attacks, per 10,000,000 Internet Hosts Averaged Over Each Quarter, as Recorded in CERT®/CC Records

Figure 11.6. Denial-of-service Attacks by Method, as Recorded in CERT®/CC Records

Figure 11.7. Primary Category of Denial-of-service Attacks, as Recorded in CERT®/CC Records

Chapter 12

Figure 12.1. Results of DISA Vulnerability Assessments, 1992 - 1995

Figure 12.2. On-Line Survey Results from 1,248 Hosts at 15 USAF Bases, Air Force Information Warfare Center, Jan 95

Figure 12.3. Estimates of the Number of Incidents per Host at Site A

Figure 12.4. Estimates of the Number of Internet Incidents based on Site A Data

Figure 12.5. Average Sites per Incident by Year

Appendix A

Figure A.1. Range and Mean Incident Start for Methods of Operation - Attackers

Figure A.2. Range and Mean Incident Start for Methods of Operation - Tools - Part 1

Figure A.3. Range and Mean Incident Start for Methods of Operation - Tools - Part 2

Figure A.4. Range and Mean Incident Start for Methods of Operation - Tools - Part 3

Figure A.5. Range and Mean Incident Start for Methods of Operation - Tools - Part 4

Figure A.6. Range and Mean Incident Start for Methods of Operation - Tools - Part 5

Figure A.7. Range and Mean Incident Start for Methods of Operation - Tools - Part 6

Figure A.8. Range and Mean Incident Start for Methods of Operation - Tools - Part 7

Figure A.9. Range and Mean Incident Start for Methods of Operation - Access - Part 1

Figure A.10. Range and Mean Incident Start for Methods of Operation - Access - Part 2

Figure A.11. Range and Mean Incident Start for Methods of Operation - Access - Part 3

Figure A.12. Range and Mean Incident Start for Methods of Operation - Access - Part 4

Figure A.13. Range and Mean Incident Start for Methods of Operation - Access - Part 5

Figure A.14. Range and Mean Incident Start for Methods of Operation - Access - Part 6

Figure A.15. Range and Mean Incident Start for Methods of Operation - Access - Part 7

Figure A.16. Range and Mean Incident Start for Methods of Operation - Access - Part 8

Figure A.17. Range and Mean Incident Start for Methods of Operation - Access - Part 9

Figure A.18. Range and Mean Incident Start for Methods of Operation - Access - Part 10

Figure A.19. Range and Mean Incident Start for Methods of Operation - Access - Part 11

Figure A.20. Range and Mean Incident Start for Methods of Operation - Access - Part 12

Figure A.21. Range and Mean Incident Start for Methods of Operation - Access - Part 13

Figure A.22. Range and Mean Incident Start for Methods of Operation - Access - Part 14

Figure A.23. Range and Mean Incident Start for Methods of Operation - Access - Part 15

Figure A.24. Range and Mean Incident Start for Methods of Operation - Access - Part 16

Figure A.25. Range and Mean Incident Start for Methods of Operation - Access - Part 17

Figure A.26. Range and Mean Incident Start for Methods of Operation - Access - Part 18

Figure A.27. Range and Mean Incident Start for Methods of Operation - Access - Part 19

Figure A.28. Range and Mean Incident Start for Methods of Operation - Access - Part 20

Figure A.29. Range and Mean Incident Start for Methods of Operation - Access - Part 21

Figure A.30. Range and Mean Incident Start for Methods of Operation - Access - Part 22

Figure A.31. Range and Mean Incident Start for Methods of Operation - Access - Part 23

Figure A.32. Range and Mean Incident Start for Methods of Operation - Access - Part 24

Figure A.33. Range and Mean Incident Start for Methods of Operation - Access - Part 25

Figure A.34. Range and Mean Incident Start for Methods of Operation - Access - Part 26

Figure A.35. Range and Mean Incident Start for Methods of Operation - Access - Part 27

Figure A.36. Range and Mean Incident Start for Methods of Operation - Access - Part 28

Figure A.37. Range and Mean Incident Start for Methods of Operation - Access - Part 29

Figure A.38. Range and Mean Incident Start for Methods of Operation - Results - Part 1

Figure A.39. Range and Mean Incident Start for Methods of Operation - Results - Part 2

Figure A.40. Range and Mean Incident Start for Methods of Operation - Results - Part 3

Figure A.41. Range and Mean Incident Start for Methods of Operation - Objectives

Appendix B

Figure B.1. Range and Mean Incident Reporting Dates for Corrective Actions - Restrict System Hardware/Software

Figure B.2. Range and Mean Incident Reporting Dates for Corrective Actions - Configure System Hardware/

Figure B.3. Range and Mean Incident Reporting Dates for Corrective Actions - Upgrade System Hardware/Software

Figure B.4. Range and Mean Incident Reporting Dates for Corrective Actions - Preventive Measures

Figure B.5. Range and Mean Incident Reporting Dates for Corrective Actions - Take Action Against Intruder

Figure B.6. Range and Mean Incident Reporting Dates for Corrective Actions - Law Enforcement


List of Tables

Chapter 2

Table 2.1. Internet Network Classes

Table 2.2. Summary of /etc/hosts file at Carnegie Mellon University, September 7, 1996

Table 2.3. Linear Regression Slopes of Growth Rates of Top-Level Internet Domains

Table 2.4. Growth of the World Wide Web

Table 2.5. Summary of Internet Growth Rates Over Six-Month Intervals

Chapter 3

Table 3.1. Internet and Other Network Response Teams in FIRST, and their Constituencies

Table 3.2. Other U.S. Government Agency Response Teams in FIRST, and their Constituencies

Table 3.3. U.S. Military Response Teams in FIRST, and their Constituencies

Table 3.4. U.S. Educational Response Teams in FIRST, with Constituencies

Table 3.5. Foreign Government Response Teams in FIRST, with Constituencies

Table 3.6. Computer and Communications Vendor Response Teams in FIRST, with Constituencies

Table 3.7. Other Commercial Response Teams in FIRST, with Constituencies

Chapter 5

Table 5.1 Example Attacks

Chapter 8

Table 8.1. Methods of Operation

Table 8.2. Corrective Actions

Chapter 9

Table 9.1. Estimated Number of Hosts at Site A

Table 9.2. Access Incidents at Site A

Table 9.3. Unauthorized Use Incidents at Site A

Chapter 10

Table 10.1. Mean and Standard Deviations of Measurements

Table 10.2. Summary of Root Break-in Incidents With 79 Days Duration, 62 Sites, 87 Messages

Table 10.3. Reporting and Other Sites for Severe Incident Number 1

Table 10.4. Reporting and Other Sites for Severe Incident Number 9

Table 10.5. Reporting and Other Sites for Severe Incident Number 2

Table 10.6. Reporting and Other Sites for Severe Incident Number 3

Table 10.7. Reporting and Other Sites for Severe Incident Number 4

Table 10.8. Reporting and Other Sites for Severe Incident Number 8

Table 10.9. Reporting and Other Sites for Severe Incident Number 5

Table 10.10. Reporting and Other Sites for Severe Incident Number 7

Table 10.11. Reporting and Other Sites for Severe Incident Number 6

Table 10.12. Reporting and Other Sites for Severe Incident Number 10

Table 10.13. Reporting and Other Sites for Severe Incident Number 11

Table 10.14. Reporting and Other Sites for Severe Incident Number 12

Table 10.15. Reporting and Other Sites for Severe Incident Number 13

Table 10.16. Reporting and Other Sites for Severe Incident Number 14

Table 10.17. Reporting and Other Sites for Severe Incident Number 17

Table 10.18. Reporting and Other Sites for Severe Incident Number 15

Table 10.19. Reporting and Other Sites for Severe Incident Number 18

Table 10.20. Reporting and Other Sites for Severe Incident Number 19

Table 10.21. Reporting and Other Sites for Severe Incident Number 21

Table 10.22. Reporting and Other Sites for Severe Incident Number 22

Table 10.23. Reporting and Other Sites for Severe Incident Number 16

Table 10.24. Reporting and Other Sites for Severe Incident Number 20

Chapter 12

Table 12.1. Estimates of Total Internet Attacks per Year in 1995

Table 12.2. Estimate of the Ratio of Total Internet Incidents to Reported Incidents

Table 12.3. All CERT®/CC Incidents Compared To Incidents at Site A

Table 12.4. Estimate of Incident Reporting Rates from Site A Data, Assuming All Root Break-ins Reported

Table 12.5. Example Weighted Estimates of Attacks per Incident

Table 12.6. Assumed Values for an Estimate of the Number of Attacks for Each CERT®/CC Incident

Table 12.7. Estimate Average Attacks/Incident Derived From Each CERT®/CC Incident Using Assumed Parameters

Table 12.8. Adjustments to the Probability of Report, Based on Site A Information

Table 12.9. Estimates of the Average Percentage of Report of an Incident and the Total Number of Internet Incidents Based on an AFWIC Estimated Average Probability of Report of Attack

Table 12.10. Estimates of the Average Probability of Report of an Incident Based on an AFWIC Estimated Average Probability of Report of Attack

Table 12.11. Estimates of the Average Percentage of Report of an Incident and the Total Number of Internet Incidents Based on an DISA Estimated Average Probability of Report of Attack

Table 12.12. Estimates of the Average Probability of Report of an Incident Based on an DISA Estimated Average Probability of Report of Attack

Table 12.13. Summary of Estimates of Total Internet Incident Activity

Table 12.14. Estimates of the Probability of Incident Report, Rate of Incident Reports, and Total Internet incidents for Incidents with Above Average Duration and Number of Sites

Table 12.15. Estimates of Total Internet Attacks per Year in 1995

Table 12.16. Summary of Estimates of Total Internet Incident Activity

Chapter 14

Table 14.1. Estimated Rate that an Internet Domain or Host was Involved in an Incident in 1995

Table 14.2. Comparison of Estimated Rates That Risks Occur

Table 14.3. Estimated Rate that an Internet Domain or Host was Involved in an Incident in 1995

Chapter 16

Table 16.1. Summary of Estimates of Total Internet Incident Activity

Table 16.2. Estimated Rate that an Internet Domain or Host was Involved in an Incident in 1995

Table 16.3. Comparison of Estimated Rates That Risks Occur

Appendix A

Table A.1. Methods of

Appendix B

Table B.1. Corrective Actions