CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003

By Jeff T. Parker and Michael Gregg

Comprehensive coverage of the new CASP+ exam, with hands-on practice and interactive study tools

The CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003, Third Edition, offers invaluable preparation for exam CAS-003. Covering 100 percent of the exam objectives, this book provides expert walk-through of essential security concepts and processes to help you tackle this challenging exam with full confidence. Practical examples and real-world insights illustrate critical topics and show what essential practices look like on the ground, while detailed explanations of technical and business concepts give you the background you need to apply identify and implement appropriate security solutions. End-of-chapter reviews help solidify your understanding of each objective, and cutting-edge exam prep software features electronic flashcards, hands-on lab exercises, and hundreds of practice questions to help you test your knowledge in advance of the exam.

The next few years will bring a 45-fold increase in digital data, and at least one third of that data will pass through the cloud. The level of risk to data everywhere is growing in parallel, and organizations are in need of qualified data security professionals; the CASP+ certification validates this in-demand skill set, and this book is your ideal resource for passing the exam.

• Master cryptography, controls, vulnerability analysis, and network security
• Identify risks and execute mitigation planning, strategies, and controls
• Analyze security trends and their impact on your organization
• Integrate business and technical components to achieve a secure enterprise architecture

CASP+ meets the ISO 17024 standard, and is approved by U.S. Department of Defense to fulfill Directive 8570.01-M requirements. It is also compliant with government regulations under the Federal Information Security Management Act (FISMA). As such, this career-building credential makes you in demand in the marketplace and shows that you are qualified to address enterprise-level security concerns. The CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003, Third Edition, is the preparation resource you need to take the next big step for your career and pass with flying colors.

• Language: English
• Publisher: Wiley
• Release date: Jan 23, 2019
• ISBN: 9781119477679

Book preview

Table of Exercises

Exercise 2.1 Sniffing VoIP Traffic

Exercise 2.2 Spoofing MAC Addresses with SMAC

Exercise 2.3 Sniffing IPv4 with Wireshark

Exercise 2.4 Capturing a Ping Packet with Wireshark

Exercise 2.5 Capturing a TCP Header with Wireshark

Exercise 2.6 Using Men & Mice to Verify DNS Configuration

Exercise 2.7 Attempting a Zone Transfer

Exercise 3.1 What Services Should Be Moved to the Cloud?

Exercise 3.2 Identifying Risks and Issues with Cloud Computing

Exercise 3.3 Turning to the Cloud for Storage and Large File Transfer

Exercise 3.4 Creating a Virtual Machine

Exercise 3.5 Understanding Online Storage

Exercise 4.1 Reviewing and Assessing ACLs

Exercise 4.2 Configuring iptables

Exercise 4.3 Testing Your Antivirus Program

Exercise 4.4 Taking Control of a Router with Physical Access

Exercise 4.5 Running a Security Scanner to Identify Vulnerabilities

Exercise 4.6 Bypassing Command Shell Restrictions

Exercise 5.1 Identifying Testing Types at Your Organization

Exercise 5.2 Downloading and Running Kali Linux

Exercise 5.3 Performing Passive Reconnaissance on Your Company or Another Organization

Exercise 5.4 Performing TCP and UDP Port Scanning

Exercise 6.1 Tracking Vulnerabilities in Software

Exercise 6.2 Outsourcing Issues to Review

Exercise 6.3 Calculating Annualized Loss Expectancy

Exercise 7.1 Reviewing Security Policy

Exercise 7.2 Reviewing Documents

Exercise 7.3 Reviewing the Employee Termination Process

Exercise 7.4 Exploring Helix, a Well-Known Forensic Tool

Exercise 8.1 Using WinDump to Sniff Traffic

Exercise 8.2 Exploring the Nagios Tool

Exercise 8.3 Using Ophcrack

Exercise 8.4 Installing Cookie Cadger

Exercise 8.5 Identifying XSS Vulnerabilities

Exercise 9.1 Reviewing Your Company’s Acceptable Use Policy

Exercise 10.1 Eavesdropping on Web Conferences

Exercise 10.2 Sniffing Email with Wireshark

Exercise 10.3 Sniffing VoIP with Cain & Abel

Introduction

The CASP+ certification was developed by the Computer Technology Industry Association (CompTIA) to provide an industry-wide means of certifying the competency of security professionals who have 10 years’ experience in IT administration and at least 5 years’ hands-on technical experience. The security professional’s job is to protect the confidentiality, integrity, and availability of an organization’s valuable information assets. As such, these individuals need to have the ability to apply critical thinking and judgment.

According to CompTIA, the CASP+ certification is a vendor-neutral credential. CASP+ validates advanced-level security skills and knowledge internationally. There is no prerequisite, but CASP+ certification is intended to follow CompTIA Security+ or equivalent experience and has a technical, ‘hands-on’ focus at the enterprise level.

Many certification books present material for you to memorize before the exam, but this book goes a step further in that it offers best practices, tips, and hands-on exercises that help those in the field of security better protect critical assets, build defense in depth, and accurately assess risk.

If you’re preparing to take the CASP+ exam, it is a good idea to find out as much information as possible about computer security practices and techniques. Because this test is designed for those with years of experience, you will be better prepared by having the most hands-on experience possible; this study guide was written with this in mind. We have included hands-on exercises, real-world scenarios, and review questions at the end of each chapter to give you some idea as to what the exam is like. You should be able to answer at least 90 percent of the test questions in this book correctly before attempting the exam; if you’re unable to do so, reread the problematic chapters and try the questions again. Your score should improve.

Before You Begin the CompTIA CASP+ Certification Exam

Before you begin studying for the exam, it’s good for you to know that the CASP+ exam is offered by CompTIA (an industry association responsible for many certifications) and is granted to those who obtain a passing score on a single exam. Before you begin studying for the exam, learn all you can about the certification.

A detailed list of the CASP+ CAS-003 (2018 Edition) exam objectives is presented in this Introduction. See the section The CASP+ (2018 Edition) Exam Objective Map.

Obtaining CASP+ certification demonstrates that you can help your organization design and maintain system and network security services designed to secure the organization’s assets. By obtaining CASP+ certification, you show that you have the technical knowledge and skills required to conceptualize, design, and engineer secure solutions across complex enterprise environments.

Who Should Read This Book

The CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003, 3rd Edition, is designed to give you the insight into the working world of IT security, and it describes the types of tasks and activities that a security professional with 5–10 years of experience carries out. Organized classes and study groups are the ideal structures for obtaining and practicing with the recommended equipment.

College classes, training classes, and boot camps are recommended ways to gain proficiency with the tools and techniques discussed in the book. However, nothing delivers hands-on learning like experiencing your own attempts, successes, and mistakes—on a home lab. More on home labs later.

What You Will Learn

This CASP+ CompTIA Advanced Security Practitioner Study Guide covers all you need to know in order to pass the CASP+ exam. The exam is based on exam objectives, and this study guide is based on the current iteration of the CASP+ exam, version CAS-003.

The latest exam version was first released in April 2018 and, if the CASP+ exam version life cycle follows the same pattern as most CompTIA exams, the CAS-003 version will remain current for about three years.

Per the CASP+ CompTIA objectives for exam version CAS-003, the five domains include the following:

Risk Management

Enterprise Security Architecture

Enterprise Security Operations

Technical Integration of Enterprise Security

Research, Development, and Collaboration

Each of these five domains further divide into 3–5 objectives. For example, the third domain, Enterprise Security Operations, is covered across three objectives:

3.1 Given a scenario, conduct a security assessment using the appropriate methods.

3.2 Analyze a scenario or output, and select the appropriate tool for a security assessment.

3.3 Given a scenario, implement incident response and recovery procedures.

These objectives read like a job task, but they are more akin to a named subset of knowledge. Many subobjectives and topics are found under each objective. These are listed hierarchically, ranging from 20 to 50 topics per objective. Yes, that’s a lot of topics when you add it all up. In short, there is a lot of material to cover. Next, we address how the book tackles it all.

How This Book Is Organized

Remember how we just explained the CASP+ exam is based on domains and objectives? Your goal for exam preparation is essentially to cover all of those subobjectives and topics. Those was our goal, too, in writing this study guide, so that’s how we structured this book—around the same exam objectives, specifically calling out every subobjective and topic. If a topic or phrase from the exam objectives list isn’t specifically called out, the concepts and understanding behind that topic or phrase are discussed thoroughly in the relevant chapter(s).

Nonetheless, CompTIA didn’t structure the exam objectives to make for good reading or an easy flow. It would be simple to tell you that each chapter correlates exactly to two or three objectives. Instead, the book is laid out to create a balance between a relevant flow of information for learning and relatable coverage of the exam objectives. This book structure then serves to be most helpful for identifying and filling any knowledge gaps that you might have in a certain area and, in turn, best prepare you for the exam.

Extra Bits

Beyond what the exam requires, there is of course some added value in the form of tips, notes, stories, and URLs where you can go for additional information online. This is typical for the Sybex study guide format. The extra bits are obviously set apart from the study guide text, and they can be enjoyed as you wish. In most cases, URLs will point to a recent news event related to the topic at hand, a link to the cited regulation, or the site where a tool can be downloaded. If a particular concept interests you, you are encouraged to follow up with that article or URL. What you will learn in this study guide is exactly what you need to know to prepare for the CASP+ certification exam. What you will learn from those tips, notes, and URLs is additional context in which the topic at hand may be better understood. Next, we discuss what you should already have in order to be successful when learning from this book.

Requirements: Practice and Experience

To be most successful in reading and learning from this book, you will need to bring something to the table yourself; that is, your experience.

Experience

You’re preparing to take one of CompTIA’s most advanced certification exams. On CompTIA’s website, they associate the CASP+ exam with the SANS Institute GIAC Certified Enterprise Defender (GCED) exam, as only these two exams focus on cybersecurity practitioner skills at an advanced level. In comparison, the CISSP and CISM exams focus on cybersecurity management skills.

The CASP+ exam covers a very wide range of information security topics. Understandably, the range is as wide as the range of information security job disciplines. As each of us grows from a junior level to the higher-level, technical lead roles, the time we spend working in one specialty area overshadows our exposure to other specialties. For example, three senior security practitioners working as an Active Directory engineer, a malware reverse engineer, and a network administrator might be highly skilled in their respective jobs yet have only a simple understanding of each other’s roles. The exam topics include specific techniques and technologies, which would be familiar to people who have held lead roles in the corresponding area of information security. Someone with experience in one or more technical areas has a great advantage, and that experience will benefit the candidate studying from this book and taking the CASP+ exam.

Last, CompTIA’s recommended level of experience is a minimum of ten years of experience in IT administration, including at least five years of hands-on technical security experience. If you have the five years, it is very likely that you have had at least minimal exposure to or understanding of most topics covered, enough for you to benefit from reading this book.

Practice

Given that the certification’s title includes the word practitioner, you are expected to have, or be capable of, building a home lab for yourself. This does not mean that you need a 42U rack full of servers and network hardware in the basement (though it might bring up a lot of excitement at home). A home lab can be as simple as having one or two virtualized machines (VMs) running on your laptop or desktop with adequate RAM. This can be done using VirtualBox or VMware Workstation Player, both of which are free. There are many pre-built VMs available online, designed specifically for security practice. A home lab can be started at no cost and be running within 15 minutes. No excuses.

Dedicating some routine time on a home lab will advance your skills and experience as well as demonstrate your passion for the subject. Current and future managers will love it! Seriously though, when you make time to build, tweak, break, and rebuild systems in your home lab, not only do you readily advance your skills and learn new technologies, but you do so without the consequences of bringing down production.

As a final note and a plug for the one of the authors’ books, Build Your Own Security Lab: A Field Guide for Network Testing by Michael Gregg (Wiley, 2008) serves as the ideal full-coverage text for this endeavor. Gregg’s book includes a DVD, and it provides enough ideas to keep you busy for years to come.

The final reason for building up a home lab is that it gives you an immediate environment on which to try out some of the tools and techniques mentioned in this CASP+ study guide. As with the experience mentioned earlier, your success on the exam is affected by how much you have learned from reading versus how much you understand from doing. The best of success to you on the exam and in your career.

How to Use This Book

Here is how the book is structured, chapter by chapter:

Chapter 1 This chapter covers cryptographic techniques, implementations of both hardware and protocols, and various cryptographic applications.

Chapter 2 A wide range of topics related to integrating network security concepts and architectures are split across this chapter, Chapter 3, and Chapter 4. This chapter includes IPv4 and IPv6 transitional technologies, SIEM, and some advanced network design.

Chapter 3 This chapter concentrates on cloud and virtualization technologies. It includes cloud service models, cloud security services, the security-related pros and cons of virtualization, and data security considerations. There is also heavy coverage of several physical and virtual network devices as they relate to security. This coverage is divided between this chapter and Chapter 4.

Chapter 4 This chapter starts with security controls for host devices. Topics include host hardening, external I/O restrictions, secure operating systems, and several variants of endpoint security software. To wrap up the wide umbrella of network security concepts and architectures, this chapter covers network access control, security zones, and network-enabled devices. Finally, the secure configuration and baselining of network devices are discussed.

Chapter 5 This chapter covers most of Domain 3 (Enterprise Security Operations), in particular the methods and tool selection for security assessments. Additionally, the chapter covers the software development life cycle as well as several development-related topics around client-side processing and server-side processing. Last, between this chapter and Chapter 9, the security controls for mobile and small form factor devices are covered.

Chapter 6 This chapter covers risk management, in particular the security risks surrounding business and industry. The chapter also discusses risk mitigation strategies and controls, including making risk determinations based on a variety of metrics, strategy recommendations based on risk appetite, and business continuity planning.

Chapter 7 This chapter covers security controls around software vulnerabilities, specific application issues, and operating system vulnerabilities. The chapter also covers material related to incident response and incident recovery. Finally, a large section of the chapter is dedicated to policies and procedures related to security, privacy, and contracts.

Chapter 8 This chapter covers research: best practices, research methods, threat intelligence, and the global security community. Additionally, there is related coverage of incident recovery in how severity is determined. This chapter also discusses the research requirements related to contracts. Last, post-incident response, lessons learned, and reporting are also covered.

Chapter 9 This chapter covers material related to how business and technology meet in the enterprise environment. In particular, the chapter addresses technical integration of hosts, storage, networks, and applications in an enterprise architecture. Also, this chapter includes coverage of the interaction between business units and their security goals. Last, enterprise mobility management is included.

Chapter 10 Advanced authentication and authorization technologies are covered in this final chapter. Additionally, the security controls related to communication and collaboration solutions are covered. Finally, the technology life cycle related to systems and emerging threats are included here.

Appendix A: Answers to Review Questions Here you’ll find the answers to the review questions that appear at the end of each chapter.

Appendix B: CASP+ Lab Manual This is a series of hands-on labs that will help you understand the key concepts presented in this book. It also includes a suggested lab setup.

About the Additional Study Tools Here you’ll find brief instructions for downloading and working effectively with this book’s additional study tools—flashcards, two 50+ question practice exams, and a glossary—available from www.sybex.com/go/casp3e.

Tips for Taking the CASP+ Exam

The CASP+ exam is a standard pass/fail exam with a maximum of 90 questions. You will have 165 minutes (2 hours, 45 minutes) to finish. There will be multiple-choice and performance-based questions (PBQs).

If you’re not familiar with PBQs but you have the recommended real-world experience, then there is little to worry about. For many candidates, PBQs are a comfortable opportunity to demonstrate experience. Unlike a multiple-choice question, the PBQ is a simulation of a scenario. The scenario is one you would likely encounter in the real world. The catch on PBQs versus multiple-choice questions is the time you spend on them. Unlike a multiple-choice question where you might spend a few seconds or a minute reading, the PBQ might involve more reading and then the time to apply or simulate the action asked of you. Luckily, the PBQs tend to occur early on in the test and you will likely only have three to five PBQs for the entire exam (but no guarantees here). Just gauge your time carefully as you progress through the exam.

Here are our tips for taking the CASP+ exam:

Bring two forms of ID with you. One must be a photo ID, such as a driver’s license. The other can be a major credit card or a passport. Both forms must include a signature.

Arrive early at the exam center. This gives you a chance to relax and, if it helps, to review any study materials you brought. Some people prefer to bring nothing, and some might want a final review of exam-related information.

When you are ready to enter the testing room, everything must go into an available locker. No material is allowed in the testing area.

Read the questions carefully. Again, carefully. Don’t be tempted to jump to an early conclusion. Know what each question is asking.

Don’t leave any unanswered questions. If you must, select your best guess and mark the question for later review.

Questions will include extra information that doesn’t apply to the actual problem (just as in the real world).

You have the option of going through the exam several times to review before you submit it, or marking questions for later review. Some people mark about 10 to 20 questions and then go back to them after they have completed all of the other questions.

Use all of your time to review, and only change your answers if you misread the question. Don’t rush through it.

Again, breathe deeply and read carefully.

For the latest pricing on the exams and updates to the registration procedures, visit CompTIA’s website at http://www.comptia.org.

How to Contact the Author

I’ve been advised not to publish my mobile phone number, so I won’t. But I do genuinely welcome anyone reaching out to me. As the author, how else can I know if anyone is actually reading this? If you are, and it’s helpful, send me a note and tell me so, at [e-mail]. Most welcome would be a note that says, Hey Jeff, I just passed my CASP+!

Sybex strives to keep you supplied with the latest tools and information you need for your work. Please check www.wiley.com/go/sybextestprep, where we’ll post additional content and updates that supplement this book should the need arise.

The CASP+ (2018 Edition) Exam Objective Map

Assessment Test

Which of the programming languages is particularly vulnerable to buffer overflows?

.NET

Pascal

C

Basic

Which of the following is not considered one of the three principles of security?

Integrity

Non-repudiation

Availability

Confidentiality

Many organizations start the preemployment process with a __________ check.

Marriage

Background

Height

Golf Handicap

In cryptography, the process of converting clear text into something that is unreadable is known as __________.

Encryption

Plain text

Digital signature

Cryptanalysis

Which transport protocol is considered connection-based?

IP

TCP

UDP

ICMP

Which of the following is not an advantage of cloud computing?

Reduced cost

The ability to access data and applications from many locations

Increased cost

The ability to pay as you go

The term ACL is most closely related to which of the following?

Hub

Switch

Bridge

Router

A __________ is used to maintain session or state when moving from one web page to another.

Browser

Cookie

Session ID

URL

In the study of cryptography, __________ is used to prove the identity of an individual.

Confidentially

Authenticity

Integrity

Availability

Kali is an example of what?

Linux bootable distribution

Session hijacking

Windows bootable preinstall program

VoIP capture tool

Which of the following is the basic transport protocol for the web?

HTTP

UDP

TFTP

FTP

Which type of attack does not give an attacker access but blocks legitimate users?

Sniffing

Session hijacking

Trojan

Denial of service

IPv4 uses addresses of what length in bits?

8

16

32

64

__________ can be used as a replacement for POP3 and offers advantages over POP3 for mobile users.

SMTP

SNMP

POP3

IMAP

What port does HTTP use by default?

53

69

80

445

Which type of agreement requires the provider to maintain a certain level of support?

MTBF

SLA

MTTR

AR

__________ is the name given to fake mail over Internet telephony.

SPAM

SPIT

SPIM

SPLAT

Which high-level document is used by management to set the overall tone in an organization?

Procedure

Guideline

Policy

Baseline

Which method of encryption makes use of a single shared key?

RSA

ECC

DES

MD5

__________ prevents one individual from having too much power in an organization.

Dual control

Separation of duties

Mandatory vacation

An NDA

__________ is an example of virtualization software.

VMware

TSWEB

LDAP

GoToMyPC

What is the purpose of Wireshark?

Sniffer

Session hijacking

Trojan

Port scanner

One area of policy compliance that many companies need to address is in meeting the credit card __________ security standards.

SOX

PCI DSS

GLB

HIPAA

The OSI model consists of how many layers?

Three

Five

Seven

Eight

Which set of regulations covers the protection of medical data and personal information?

HIPAA

GLBA

SOX

GDPR

____________ is a well-known incident response, computer forensic, and e-discovery tool.

PuTTY

Hunt

Firesheep

Helix3

Shawn downloads a program for his iPhone that is advertised as a game yet actually tracks his location and browser activity. This is best described as a __________?

Virus

Worm

Trojan

Spam

__________ is used to send mail and to relay mail to other SMTP mail servers and uses port 25 by default.

SMTP

SNMP

POP3

IMAP

__________ is used to prevent a former employee from releasing confidential information to a third party.

Dual control

Separation of duty

Mandatory vacation

NDA

Which technique helps detect if an employee is involved in malicious activity?

Dual controls

Separation of duties

Mandatory vacations

NDAs

Answers to Assessment Test

C. The C programming language is particularly vulnerable to buffer overflows. This is because some functions do not perform proper bounds checking. (Chapter 5)

B. Non-repudiation is not considered one of the three principles of security. (Chapter 1)

B. Many organizations start the preemployment process with a background check. This process is done to make sure the right person is hired for the job. (Chapter 7)

A. In cryptography, the process of converting clear text into something that is unreadable is known as encryption. (Chapter 1)

B. TCP is considered a connection-based protocol, whereas UDP is considered connectionless. (Chapter 2)

C. Although there are many benefits to cloud computing, increased cost is not one of them. Cloud computing is designed to lower costs. (Chapter 3)

D. The term ACL is most closely related to a router. ACLs are used as a basic form of firewall traffic control. (Chapter 4)

B. A cookie is used to maintain state when moving from one web page to another. (Chapter 5)

B. In the study of cryptography, authenticity is used to prove the identity of an individual. (Chapter 1)

A. Kali is an example of a Linux bootable distribution. It is one of the items on the CASP+ tools and technology list. (Chapter 8)

A. HTTP is the basic transport protocol for the web. HTTP uses TCP as a transport. (Chapter 2)

D. A denial of service does not give an attacker access but blocks legitimate users. (Chapter 6)

C. IPv4 uses 32-bit addresses, whereas IPv6 uses 128-bit addresses. (Chapter 2)

D. IMAP can be used as a replacement for POP3, and it offers advantages over POP3 for mobile users, such as remote mail and folder management, so it’s easier to view from multiple locations. (Chapter 10)

C. HTTP uses port 80 by default. (Chapter 4)

B. A service level agreement (SLA) requires the provider to maintain a certain level of support. (Chapter 7)

B. The acronym SPIT stands for Spam over Internet Telephony. (Chapter 10)

C. A policy is a high-level document used by management to set the overall tone. (Chapter 7)

C. DES makes use of a single shared key, and it is an example of symmetric encryption. (Chapter 1)

B. Separation of duties prevents one individual from having too much power. (Chapter 7)

A. VMware is an example of virtualization. These tools are very popular today, and they are required knowledge for the CASP+ exam. (Chapter 3)

A. Wireshark is a well-known open-source packet capture and sniffer program. Although packet sniffers are not malicious tools, they can be used to capture clear-text usernames and passwords. (Chapter 5)

B. One area of policy compliance that many companies need to address is in meeting the Payment Card Industry Data Security Standard (PCI DSS). (Chapter 7)

C. The OSI model consists of seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. (Chapter 2)

A. HIPAA covers the protection of medical data and personal information. (Chapter 6)

D. Helix3 is a well-known incident response, computer forensic, and e-discovery tool. Helix is required knowledge for the exam. (Chapter 8)

C. Shawn downloads a program for his iPhone that is advertised as a game yet actually tracks his location and browser activity. This is best described as a Trojan. Trojans typically present themselves as something the user wants, when in fact they are malicious. (Chapter 4)

A. SMTP is used to send mail and to relay mail to other SMTP mail servers and uses port 25 by default. You should have a basic understanding of common ports and applications such as SMTP, POP3, and IMAP for the exam. (Chapter 10)

D. A nondisclosure agreement (NDA) is used to prevent a former employee from releasing confidential information to a third party. (Chapter 7)

C. Mandatory vacations allow for the review of an employee’s duties while they are not on duty. (Chapter 9)

Chapter 1

Cryptographic Tools and Techniques

THE FOLLOWING COMPTIA CASP+ EXAM OBJECTIVES ARE COVERED IN THIS CHAPTER:

2.1 Analyze a scenario and integrate network and security components, concepts and architectures to meet security requirements.

2.1 Analyze a scenario and integrate network and security components, concepts and architectures to meet security requirements.

Physical and virtual network and security devices

HSM

2.3 Analyze a scenario to integrate security controls for mobile and small form factor devices to meet security requirements.

Security implications/privacy concerns

TPM

4.4 Given a scenario, implement cryptographic techniques.

Techniques

Key stretching

Hashing

Digital signature

Message authentication

Code signing

Pseudo-random number generation

Perfect forward secrecy

Data-at-rest encryption

Disk

Block

File

Record

Steganography

Implementations

DRM

Watermarking

GPG

SSL/TLS

SSH

S/MIME

Cryptographic applications and proper/improper implementations

Strength

Performance

Feasibility to implement

Interoperability

Stream vs. block

PKI

Wild card

OCSP vs. CRL

Issuance to entities

Key escrow

Certificate

Tokens

Stapling

Pinning

Cryptocurrency/blockchain

This chapter discusses cryptography, which can be defined as the art of protecting information by transforming it into an unreadable format. Everywhere you turn you see cryptography. It is used to protect sensitive information, prove the identity of a claimant, and verify the integrity of an application or program. As a security professional for your company, which of the following would you consider more critical if you could choose only one?

Provide a locking cable for every laptop user in the organization.

Enforce full disk encryption for every mobile device.

Our choice would be full disk encryption. Typically, the data will be worth more than the cost of a replacement laptop. If the data is lost or exposed, you’ll incur additional costs such as client notification and reputation loss.

As a security professional, you should have a good basic understanding of cryptographic functions. This chapter begins by reviewing a little of the history of cryptography. Next, we discuss basic cryptographic types, explaining symmetric and asymmetric encryption, hashing, digital signatures, and public key infrastructure. These concepts are important as we move on to more advanced topics and begin to look at cryptographic applications. Understanding them will help you prepare for the CompTIA exam and to implement cryptographic solutions to protect your company’s assets better.

The History of Cryptography

Encryption is not a new concept. The desire to keep secrets is as old as civilization. There are two basic ways in which encryption is used: for data at rest and for data in motion. Data at rest might be information on a laptop hard drive or in cloud storage. Data in motion might be data being processed by SQL, a URL requested via HTTP, or information traveling over a VPN at the local coffee shop bound for the corporate network. In each of these cases, protection must be sufficient. The following list includes some examples of early cryptographic systems:

Scytale This system functioned by wrapping a strip of papyrus or leather, on which a message was written, around a rod of fixed diameter. The recipient used a rod of the same diameter to read the message. Although such systems seem basic today, it worked well in the time of the Spartans. Even if someone was to intercept the message, it appeared as a jumble of meaningless letters.

Caesar’s Cipher Julius Caesar is known for an early form of encryption, the Caesar cipher, which was used to transmit messages sent between Caesar and his generals. The cipher worked by means of a simple substitution. Before a message was sent, the plain text was rotated forward by three characters (ROT3). Using Caesar’s cipher to encrypt the word cat would result in fdw. Decrypting required moving back three characters.

Other Examples Substitution ciphers replace one character for another. The best example of a substitution cipher is the Vigenère polyalphabetic cipher. Other historical systems include a running key cipher and the Vernam cipher. The running key cipher is another way to generate the keystream for use with the tabula recta. The Vernam is also known as the onetime pad.

Cryptographic Services

As a security professional, you need to understand cryptographic services and how they are applied. You also need to know the goals of cryptography and basic terms. Although your job may not require you to be a cryptographic expert, to pass the CASP+ exam you should be able to explain how specific cryptographic functions work.

Cryptographic Goals

Cryptography includes methods such as symmetric encryption, asymmetric encryption, hashing, and digital signatures. Each provides specific attributes and solutions. These cryptographic services include the following goals:

Privacy Also called confidentiality. What is private (confidential) should stay private, whether at rest or in transit.

Authentication There should be proof that the message is from the person or entity you believe it to be from.

Integrity Information should remain unaltered at the point at which it was produced, while it is in transmission, and during storage.

Non-repudiation The sender of data is provided with proof of delivery, and the recipient is assured of the sender’s identity.

An easy way to remember these items for the exam is to think of PAIN. This simple acronym (privacy, authentication, integrity, and non-repudiation) should help you remember the basic cryptographic goals.

Knowing these basic goals can go a long way in helping you to understand that cryptography can be used as a tool to achieve confidentially, integrity, and availability. For example, consider how encryption can protect the privacy and confidentiality of information at rest or in transit. What if your CEO has been asked to travel to the Far East for trade negotiations? Think about the CEO’s laptop. If it is lost or compromised, how hard would it be for someone to remove unencrypted data? Strong encryption offers an easy way to protect that information should the equipment be lost, stolen, or accessed by unauthorized individuals. Applications such as CryptoForge and BitLocker offer the ability to encrypt a hard drive. PKWare provides users with enterprise data security that persistently protects and manages data whenever it is used, shared, and stored, both inside and outside the organization. Sookasa transparently protects files across the Dropbox and Google Drive clouds as well as linked mobile devices while preserving the native user experience on the Windows, MacOS, iOS, and Android operating systems.

During a trip to Beijing in December 2007, it was discovered that someone had accessed a laptop used by former Commerce Secretary Carlos Gutierrez and had placed monitoring programs on it designed to secretly remove information. Read more at http://fortune.com/2016/07/27/ceo-twitter-hack-list/.

Authentication is another key goal of cryptography. First, authentication is associated with digital signatures. Authentication provides a way to ensure that a message is from whom we believe it’s from. In its basic form, authentication is used to determine identity. It is also part of the identification and authentication process.

Integrity is another cryptographic goal. Integrity is important while data is in transmission and in storage. Integrity means that information remains unaltered. Imagine the situation of needing to download a patch. Although the patch is available on the developer’s site, you also have a copy on DVD that was given to you by a colleague. Is the version on the DVD the same as the one on the developer’s website? Integrity verification programs that perform hashing such as MD5 or SHA can help you determine this.

Non-repudiation is assurance that an entity in a communication cannot deny authenticity. It is proof of the veracity of a claim. Non-repudiation means that a sender of data receives proof of delivery and the recipient is assured of the sender’s identity. Neither party should be able to deny having sent or received the data at a later date. This can be achieved with digital signatures. A digital signature provides authenticity, integrity, and non-repudiation. In the days of face-to-face transactions, non-repudiation was not as hard to prove. Today, the Internet makes many transactions faceless. We may never see the people we deal with; therefore, non-repudiation becomes all the more critical. Non-repudiation is achieved through digital signatures, digital certificates, and message authentication codes (MACs).

When implementing a cryptographic system, there has to be consideration of strength versus performance versus feasibility to implement versus interoperability. Stronger systems typically require more process power and longer encryption/decryption times. Basically, you must consider how strong an encryption process should be. The strength of a cryptosystem relies on the strength of an algorithm and the complexity of the key generation process. The strength of the encryption mechanism also rests on the size and complexity of the key. If the cryptosystem uses a weak key generation process, then the entire process is weak. The key size goes a long way in determining the strength of the cryptosystem.

The designer of a cryptographic system must also understand the implications of cryptographic methods and design. As an example, Caesar might have thought his system of encryption was quite strong, but it would be seen as relativity insecure today. You need a sufficiently sized key to deter brute-force and other attacks. In the world of cryptography, key lengths are defined by the number of binary bits. So, a 64-bit key has a keyspace of 2 to the power of 64, or 18,446,744,073,709,551,616.

Cryptographic Terms

As a security professional, you need to understand basic cryptographic terms. You will encounter these terms when examining a vendor’s security solution, discussing security controls with colleagues, and implementing a security solution. Here are some basic cryptographic terms:

Plain Text Clear text that is readable

Cipher Text Encrypted text that is unreadable

Encryption Transforming data into an unreadable format. For example, using Caesar’s cipher to encrypt the word dog would result in grj. Encryption here has moved each character forward by three letters.

Cryptanalysis The act of obtaining plain text from cipher text without a cryptographic key. It is used by governments, the military, enterprises, ethical hackers, and malicious hackers to find weaknesses and crack cryptographic systems.

Digital Signature A hash value that has been encrypted with the private key of the sender. It is used for authentication and integrity.

Chain of Trust The relationship between subordinate certificate authorities. The concept of chain of trust is critical in the world of public key infrastructure as it provides a means to pass trust from one entity to another. It allows the delegation of certificate duties to a subordinate certificate authority.

Root of Trust Root of trust can be described as the concept of trust in a system, software, or data. It is the most common form of attestation, and it provides a basic set of functions that are always trusted by the operating system. Attestation means that you are validating something as true. A root of trust can be designed as hardware-based, software-based, or hybrid. The Trusted Platform Module (TPM) is one of the most common.

Think of root of trust as something that has been deemed trustworthy. As an example, if you are asked to serve on the jury of a court case, the lawyers should be seen as trustworthy. That’s because the court trusts that the lawyers are licensed to practice law in the state and that a client-to-lawyer relationship has been established by the legal system and because the court uses a well-defined procedural process for evidence to be admitted. Although computer systems don’t need lawyers, let’s hope, they do need trust, and that is the role that TPM plays. TPM has a root of trust that is defined by the endorsement key (EK) pair. It is a unique RSA key found within all TPM devices.

Cryptographic systems can be broadly classified into symmetric, asymmetric, and hashing:

Symmetric Cryptography This type uses a single private key.

Asymmetric Cryptography This type uses two keys: a public key known to everyone and a private key that only the recipient of messages uses.

Although both concepts are discussed in more detail later in the chapter, at this point it’s important to understand that both symmetric and asymmetric cryptography make use of a key. The key is input into the encryption algorithm as data on which to perform mathematical operations such as permutation, substitution, or binary math.

Hash A hash is a defined mathematical procedure or function that converts a large amount of data into a fixed small string of data or integer. The output of a hash is known as a hash value, hash code, hash sum, checksum, fingerprint, or message digest.

For the CASP+ exam, more than one term may be used to describe a hash.

Here are some other terms that you will need to know for the exam:

Algorithm An algorithm is a set of rules or ordered steps used to encrypt and decrypt data. The algorithm is a set of instructions used with the cryptographic key to encrypt plain text data. Plain text data encrypted with different keys or dissimilar algorithms will produce different cipher text.

Cipher Text Cipher text is data that is scrambled and unreadable. When plain text is converted into cipher text, the transformation can be