
- •Acknowledgments
- •About the Authors
- •About the Technical Editors
- •Contents at a Glance
- •Contents
- •Foreword
- •Introduction
- •Overview of the CISSP Exam
- •The Elements of This Study Guide
- •Study Guide Exam Objectives
- •Objective Map
- •Reader Support for This Book
- •Security 101
- •Confidentiality
- •Integrity
- •Availability
- •Protection Mechanisms
- •Security Boundaries
- •Third-Party Governance
- •Documentation Review
- •Manage the Security Function
- •Alignment of Security Function to Business Strategy, Goals, Mission, and Objectives
- •Organizational Processes
- •Organizational Roles and Responsibilities
- •Security Control Frameworks
- •Due Diligence and Due Care
- •Security Policy, Standards, Procedures, and Guidelines
- •Security Policies
- •Security Standards, Baselines, and Guidelines
- •Security Procedures
- •Threat Modeling
- •Identifying Threats
- •Determining and Diagramming Potential Attacks
- •Performing Reduction Analysis
- •Prioritization and Response
- •Supply Chain Risk Management
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Job Descriptions and Responsibilities
- •Candidate Screening and Hiring
- •Onboarding: Employment Agreements and Policies
- •Employee Oversight
- •Compliance Policy Requirements
- •Privacy Policy Requirements
- •Understand and Apply Risk Management Concepts
- •Risk Terminology and Concepts
- •Asset Valuation
- •Identify Threats and Vulnerabilities
- •Risk Assessment/Analysis
- •Risk Responses
- •Cost vs. Benefit of Security Controls
- •Countermeasure Selection and Implementation
- •Applicable Types of Controls
- •Security Control Assessment
- •Monitoring and Measurement
- •Risk Reporting and Documentation
- •Continuous Improvement
- •Risk Frameworks
- •Social Engineering
- •Social Engineering Principles
- •Eliciting Information
- •Prepending
- •Phishing
- •Spear Phishing
- •Whaling
- •Smishing
- •Vishing
- •Spam
- •Shoulder Surfing
- •Invoice Scams
- •Hoax
- •Impersonation and Masquerading
- •Tailgating and Piggybacking
- •Dumpster Diving
- •Identity Fraud
- •Typo Squatting
- •Influence Campaigns
- •Awareness
- •Training
- •Education
- •Improvements
- •Effectiveness Evaluation
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Planning for Business Continuity
- •Project Scope and Planning
- •Organizational Review
- •BCP Team Selection
- •Resource Requirements
- •Legal and Regulatory Requirements
- •Business Impact Analysis
- •Identifying Priorities
- •Risk Identification
- •Likelihood Assessment
- •Impact Analysis
- •Resource Prioritization
- •Continuity Planning
- •Strategy Development
- •Provisions and Processes
- •Plan Approval and Implementation
- •Plan Approval
- •Plan Implementation
- •Training and Education
- •BCP Documentation
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Categories of Laws
- •Criminal Law
- •Civil Law
- •Administrative Law
- •Laws
- •Computer Crime
- •Intellectual Property (IP)
- •Licensing
- •Import/Export
- •Privacy
- •State Privacy Laws
- •Compliance
- •Contracting and Procurement
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Defining Sensitive Data
- •Defining Data Classifications
- •Defining Asset Classifications
- •Understanding Data States
- •Determining Compliance Requirements
- •Determining Data Security Controls
- •Data Maintenance
- •Data Loss Prevention
- •Marking Sensitive Data and Assets
- •Handling Sensitive Information and Assets
- •Data Collection Limitation
- •Data Location
- •Storing Sensitive Data
- •Data Destruction
- •Ensuring Appropriate Data and Asset Retention
- •Data Protection Methods
- •Digital Rights Management
- •Cloud Access Security Broker
- •Pseudonymization
- •Tokenization
- •Anonymization
- •Understanding Data Roles
- •Data Owners
- •Asset Owners
- •Business/Mission Owners
- •Data Processors and Data Controllers
- •Data Custodians
- •Administrators
- •Users and Subjects
- •Using Security Baselines
- •Comparing Tailoring and Scoping
- •Standards Selection
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Cryptographic Foundations
- •Goals of Cryptography
- •Cryptography Concepts
- •Cryptographic Mathematics
- •Ciphers
- •Modern Cryptography
- •Cryptographic Keys
- •Symmetric Key Algorithms
- •Asymmetric Key Algorithms
- •Hashing Algorithms
- •Symmetric Cryptography
- •Cryptographic Modes of Operation
- •Data Encryption Standard
- •Triple DES
- •International Data Encryption Algorithm
- •Blowfish
- •Skipjack
- •Rivest Ciphers
- •Advanced Encryption Standard
- •CAST
- •Comparison of Symmetric Encryption Algorithms
- •Symmetric Key Management
- •Cryptographic Lifecycle
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Asymmetric Cryptography
- •Public and Private Keys
- •ElGamal
- •Elliptic Curve
- •Diffie–Hellman Key Exchange
- •Quantum Cryptography
- •Hash Functions
- •RIPEMD
- •Comparison of Hash Algorithm Value Lengths
- •Digital Signatures
- •HMAC
- •Digital Signature Standard
- •Public Key Infrastructure
- •Certificates
- •Certificate Authorities
- •Certificate Lifecycle
- •Certificate Formats
- •Asymmetric Key Management
- •Hybrid Cryptography
- •Applied Cryptography
- •Portable Devices
- •Web Applications
- •Steganography and Watermarking
- •Networking
- •Emerging Applications
- •Cryptographic Attacks
- •Salting Saves Passwords
- •Ultra vs. Enigma
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Secure Design Principles
- •Objects and Subjects
- •Closed and Open Systems
- •Secure Defaults
- •Fail Securely
- •Keep It Simple
- •Zero Trust
- •Privacy by Design
- •Trust but Verify
- •Techniques for Ensuring CIA
- •Confinement
- •Bounds
- •Isolation
- •Access Controls
- •Trust and Assurance
- •Trusted Computing Base
- •State Machine Model
- •Information Flow Model
- •Noninterference Model
- •Take-Grant Model
- •Access Control Matrix
- •Bell–LaPadula Model
- •Biba Model
- •Clark–Wilson Model
- •Brewer and Nash Model
- •Goguen–Meseguer Model
- •Sutherland Model
- •Graham–Denning Model
- •Harrison–Ruzzo–Ullman Model
- •Select Controls Based on Systems Security Requirements
- •Common Criteria
- •Authorization to Operate
- •Understand Security Capabilities of Information Systems
- •Memory Protection
- •Virtualization
- •Trusted Platform Module
- •Interfaces
- •Fault Tolerance
- •Encryption/Decryption
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Shared Responsibility
- •Hardware
- •Firmware
- •Client-Based Systems
- •Mobile Code
- •Local Caches
- •Server-Based Systems
- •Large-Scale Parallel Data Systems
- •Grid Computing
- •Peer to Peer
- •Industrial Control Systems
- •Distributed Systems
- •Internet of Things
- •Edge and Fog Computing
- •Static Systems
- •Network-Enabled Devices
- •Cyber-Physical Systems
- •Elements Related to Embedded and Static Systems
- •Security Concerns of Embedded and Static Systems
- •Specialized Devices
- •Microservices
- •Infrastructure as Code
- •Virtualized Systems
- •Virtual Software
- •Virtualized Networking
- •Software-Defined Everything
- •Virtualization Security Management
- •Containerization
- •Serverless Architecture
- •Mobile Devices
- •Mobile Device Security Features
- •Mobile Device Deployment Policies
- •Process Isolation
- •Hardware Segmentation
- •System Security Policy
- •Covert Channels
- •Attacks Based on Design or Coding Flaws
- •Rootkits
- •Incremental Attacks
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Apply Security Principles to Site and Facility Design
- •Secure Facility Plan
- •Site Selection
- •Facility Design
- •Equipment Failure
- •Wiring Closets
- •Server Rooms/Data Centers
- •Intrusion Detection Systems
- •Cameras
- •Access Abuses
- •Media Storage Facilities
- •Evidence Storage
- •Restricted and Work Area Security
- •Utility Considerations
- •Fire Prevention, Detection, and Suppression
- •Perimeter Security Controls
- •Internal Security Controls
- •Key Performance Indicators of Physical Security
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •OSI Model
- •History of the OSI Model
- •OSI Functionality
- •Encapsulation/Deencapsulation
- •OSI Layers
- •TCP/IP Model
- •Common Application Layer Protocols
- •SNMPv3
- •Transport Layer Protocols
- •Domain Name System
- •DNS Poisoning
- •Domain Hijacking
- •Internet Protocol (IP) Networking
- •IP Classes
- •ICMP
- •IGMP
- •ARP Concerns
- •Secure Communication Protocols
- •Implications of Multilayer Protocols
- •Converged Protocols
- •Voice over Internet Protocol (VoIP)
- •Software-Defined Networking
- •Microsegmentation
- •Wireless Networks
- •Securing the SSID
- •Wireless Channels
- •Conducting a Site Survey
- •Wireless Security
- •Wi-Fi Protected Setup (WPS)
- •Wireless MAC Filter
- •Wireless Antenna Management
- •Using Captive Portals
- •General Wi-Fi Security Procedure
- •Wireless Communications
- •Wireless Attacks
- •Other Communication Protocols
- •Cellular Networks
- •Content Distribution Networks (CDNs)
- •Secure Network Components
- •Secure Operation of Hardware
- •Common Network Equipment
- •Network Access Control
- •Firewalls
- •Endpoint Security
- •Transmission Media
- •Network Topologies
- •Ethernet
- •Sub-Technologies
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Protocol Security Mechanisms
- •Authentication Protocols
- •Port Security
- •Quality of Service (QoS)
- •Secure Voice Communications
- •Voice over Internet Protocol (VoIP)
- •Vishing and Phreaking
- •PBX Fraud and Abuse
- •Remote Access Security Management
- •Remote Connection Security
- •Plan a Remote Access Security Policy
- •Multimedia Collaboration
- •Remote Meeting
- •Instant Messaging and Chat
- •Load Balancing
- •Virtual IPs and Load Persistence
- •Active-Active vs. Active-Passive
- •Manage Email Security
- •Email Security Goals
- •Understand Email Security Issues
- •Email Security Solutions
- •Virtual Private Network
- •Tunneling
- •How VPNs Work
- •Always-On
- •Common VPN Protocols
- •Switching and Virtual LANs
- •Switch Eavesdropping
- •Private IP Addresses
- •Stateful NAT
- •Automatic Private IP Addressing
- •Third-Party Connectivity
- •Circuit Switching
- •Packet Switching
- •Virtual Circuits
- •Fiber-Optic Links
- •Security Control Characteristics
- •Transparency
- •Transmission Management Mechanisms
- •Prevent or Mitigate Network Attacks
- •Eavesdropping
- •Modification Attacks
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Controlling Access to Assets
- •Controlling Physical and Logical Access
- •The CIA Triad and Access Controls
- •Managing Identification and Authentication
- •Comparing Subjects and Objects
- •Registration, Proofing, and Establishment of Identity
- •Authorization and Accountability
- •Authentication Factors Overview
- •Something You Know
- •Something You Have
- •Something You Are
- •Multifactor Authentication (MFA)
- •Two-Factor Authentication with Authenticator Apps
- •Passwordless Authentication
- •Device Authentication
- •Service Authentication
- •Mutual Authentication
- •Implementing Identity Management
- •Single Sign-On
- •SSO and Federated Identities
- •Credential Management Systems
- •Credential Manager Apps
- •Scripted Access
- •Session Management
- •Provisioning and Onboarding
- •Deprovisioning and Offboarding
- •Defining New Roles
- •Account Maintenance
- •Account Access Review
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Comparing Access Control Models
- •Comparing Permissions, Rights, and Privileges
- •Understanding Authorization Mechanisms
- •Defining Requirements with a Security Policy
- •Introducing Access Control Models
- •Discretionary Access Control
- •Nondiscretionary Access Control
- •Implementing Authentication Systems
- •Implementing SSO on the Internet
- •Implementing SSO on Internal Networks
- •Understanding Access Control Attacks
- •Crackers, Hackers, and Attackers
- •Risk Elements
- •Common Access Control Attacks
- •Core Protection Methods
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Security Testing
- •Security Assessments
- •Security Audits
- •Performing Vulnerability Assessments
- •Describing Vulnerabilities
- •Vulnerability Scans
- •Penetration Testing
- •Compliance Checks
- •Code Review and Testing
- •Interface Testing
- •Misuse Case Testing
- •Test Coverage Analysis
- •Website Monitoring
- •Implementing Security Management Processes
- •Log Reviews
- •Account Management
- •Disaster Recovery and Business Continuity
- •Training and Awareness
- •Key Performance and Risk Indicators
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Need to Know and Least Privilege
- •Separation of Duties (SoD) and Responsibilities
- •Two-Person Control
- •Job Rotation
- •Mandatory Vacations
- •Privileged Account Management
- •Service Level Agreements (SLAs)
- •Addressing Personnel Safety and Security
- •Duress
- •Travel
- •Emergency Management
- •Security Training and Awareness
- •Provision Resources Securely
- •Information and Asset Ownership
- •Asset Management
- •Apply Resource Protection
- •Media Management
- •Media Protection Techniques
- •Managed Services in the Cloud
- •Shared Responsibility with Cloud Service Models
- •Scalability and Elasticity
- •Provisioning
- •Baselining
- •Using Images for Baselining
- •Automation
- •Managing Change
- •Change Management
- •Versioning
- •Configuration Documentation
- •Managing Patches and Reducing Vulnerabilities
- •Systems to Manage
- •Patch Management
- •Vulnerability Management
- •Vulnerability Scans
- •Common Vulnerabilities and Exposures
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Conducting Incident Management
- •Defining an Incident
- •Incident Management Steps
- •Basic Preventive Measures
- •Understanding Attacks
- •Intrusion Detection and Prevention Systems
- •Specific Preventive Measures
- •Logging and Monitoring
- •The Role of Monitoring
- •Log Management
- •Egress Monitoring
- •Automating Incident Response
- •Understanding SOAR
- •Threat Intelligence
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •The Nature of Disaster
- •Natural Disasters
- •Human-Made Disasters
- •Protecting Hard Drives
- •Protecting Servers
- •Protecting Power Sources
- •Trusted Recovery
- •Quality of Service
- •Recovery Strategy
- •Business Unit and Functional Priorities
- •Crisis Management
- •Emergency Communications
- •Workgroup Recovery
- •Alternate Processing Sites
- •Database Recovery
- •Recovery Plan Development
- •Emergency Response
- •Personnel and Communications
- •Assessment
- •Backups and Off-site Storage
- •Software Escrow Arrangements
- •Utilities
- •Logistics and Supplies
- •Recovery vs. Restoration
- •Testing and Maintenance
- •Structured Walk-Through
- •Simulation Test
- •Parallel Test
- •Lessons Learned
- •Maintenance
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Investigations
- •Investigation Types
- •Evidence
- •Investigation Process
- •Major Categories of Computer Crime
- •Military and Intelligence Attacks
- •Business Attacks
- •Financial Attacks
- •Terrorist Attacks
- •Grudge Attacks
- •Thrill Attacks
- •Hacktivists
- •Ethics
- •Organizational Code of Ethics
- •(ISC)2 Code of Ethics
- •Ethics and the Internet
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Software Development
- •Systems Development Lifecycle
- •Lifecycle Models
- •Gantt Charts and PERT
- •Change and Configuration Management
- •The DevOps Approach
- •Application Programming Interfaces
- •Software Testing
- •Code Repositories
- •Service-Level Agreements
- •Third-Party Software Acquisition
- •Establishing Databases and Data Warehousing
- •Database Management System Architecture
- •Database Transactions
- •Security for Multilevel Databases
- •Open Database Connectivity
- •NoSQL
- •Expert Systems
- •Machine Learning
- •Neural Networks
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Malware
- •Sources of Malicious Code
- •Viruses
- •Logic Bombs
- •Trojan Horses
- •Worms
- •Spyware and Adware
- •Ransomware
- •Malicious Scripts
- •Zero-Day Attacks
- •Malware Prevention
- •Platforms Vulnerable to Malware
- •Antimalware Software
- •Integrity Monitoring
- •Advanced Threat Protection
- •Application Attacks
- •Buffer Overflows
- •Time of Check to Time of Use
- •Backdoors
- •Privilege Escalation and Rootkits
- •Injection Vulnerabilities
- •SQL Injection Attacks
- •Code Injection Attacks
- •Command Injection Attacks
- •Exploiting Authorization Vulnerabilities
- •Insecure Direct Object References
- •Directory Traversal
- •File Inclusion
- •Request Forgery
- •Session Hijacking
- •Application Security Controls
- •Input Validation
- •Web Application Firewalls
- •Database Security
- •Code Security
- •Secure Coding Practices
- •Source Code Comments
- •Error Handling
- •Hard-Coded Credentials
- •Memory Management
- •Summary
- •Exam Essentials
- •Written Lab
- •Review Questions
- •Chapter 2: Personnel Security and Risk Management Concepts
- •Chapter 3: Business Continuity Planning
- •Chapter 4: Laws, Regulations, and Compliance
- •Chapter 5: Protecting Security of Assets
- •Chapter 10: Physical Security Requirements
- •Chapter 11: Secure Network Architecture and Components
- •Chapter 12: Secure Communications and Network Attacks
- •Chapter 17: Preventing and Responding to Incidents
- •Chapter 18: Disaster Recovery Planning
- •Chapter 19: Investigations and Ethics
- •Chapter 20: Software Development Security
- •Chapter 21: Malicious Code and Application Attacks
- •Chapter 3: Business Continuity Planning
- •Chapter 5: Protecting Security of Assets
- •Chapter 6: Cryptography and Symmetric Key Algorithms
- •Chapter 12: Secure Communications and Network Attacks
- •Chapter 15: Security Assessment and Testing
- •Chapter 17: Preventing and Responding to Incidents
- •Chapter 18: Disaster Recovery Planning
- •Chapter 19: Investigations and Ethics
- •Chapter 21: Malicious Code and Application Attacks
- •Index

616 Chapter 12 ■ Secure Communications and Network Attacks
Another issue to be familiar with is that of NAT traversal (NAT-T) (RFC 3947). Traditional NAT doesn’t support IPsec VPNs, because of the requirements of the IPsec protocol and the changes NAT makes to packet headers (which is perceived as corruption or violating integrity). However, NAT-T was designed specifically to support IPsec and other tunneling VPN protocols, such as Layer 2 Tunneling Protocol (L2TP), so that organizations can benefit from both NAT and VPNs across the same border device/interface.
Although NAT by default is a dynamic outbound mapping mechanism, it can be configured to perform inbound mapping as well. Known as static NAT, reverse proxy, port forwarding, or destination network address translation (DNAT), this technique allows an external entity to initiate communication with an internal entity behind a NAT by using a public socket that is mapped to redirect to an internal system’s private address. Though this is technically possible, it is generally to be avoided. Granting the easy ability for an external entity to initiate a connection with an internal system is not usually a secure solution. Static NAT may be useful for systems in a screened subnet or extranet, but definitely not for accessing systems in the internal private LAN.
NAT is not used with IPv6, but there are IPv4-to-IPv6 gateways that are sometimes called NAT solutions, but they are technical protocol translation gateways rather than just address translation services.
Private IP Addresses
With only roughly 4 billion addresses (232) available in IPv4, the world has simply deployed more devices using IPv4 than there are unique IPv4 addresses available. Fortunately, the early designers of the internet and TCP/IP had good foresight and put aside a few blocks of addresses for private, unrestricted use. These IPv4 addresses, commonly called the private IPv4 addresses, are defined in RFC 1918. They are as follows:
■■
■■
■■
10.0.0.0–10.255.255.255 (a full Class A range) 172.16.0.0–172.31.255.255 (16 Class B ranges) 192.168.0.0–192.168.255.255 (256 Class C ranges)
Can’t NAT Again!
On several occasions we’ve needed to “re-NAT” an already “NATed” network.This might occur in the following situations:
■■You need to make an isolated subnet within a NATed network and attempt to do so by connecting a router to host your new subnet to the single port offered by the existing network.
■■You have a DSL or cable modem that offers only a single connection but you have multiple computers or want to add wireless to your environment.

Network AddressTranslation |
617 |
By connecting a NAT proxy router or a wireless access point, you are usually attempting to re-NAT what was NATed to you initially. One configuration setting that can either make or break this setup is the IPv4 address range in use. It is not possible to re-NAT the same subnet. For example, if your existing network is offering 192.168.1.x addresses, then you cannot use that same address range in your new NATed subnet. So change the configuration of your new router/WAP to perform NAT on a slightly different address range, such as 192.168.5.x, and you won’t have the conflict.This seems obvious, but it is quite frustrating to troubleshoot the unwanted result without this insight.
All routers and traffic-directing devices are configured by default not to forward traffic to or from these IPv4 addresses. In other words, the private IPv4 addresses are not routed by default. Thus, they cannot be directly used to communicate over the internet. However, they can be easily used on private networks where routers are not employed or where slight modifications to router configurations are made. Using private IPv4 addresses in conjunction with NAT greatly reduces the cost of connecting to the internet by allowing fewer public IPv4 addresses to be leased from an ISP.
Attempting to use the RFC 1918 private IPv4 addresses directly on the internet is futile because all publicly accessible routers will drop data packets containing a source IPv4 address from these RFC 1918 ranges.
Stateful NAT
NAT operates by maintaining a mapping between requests made by internal clients, a client’s internal IP address, and the IP address of the internet service contacted. When a request packet is received by NAT from a client, it changes the source address in the packet from the client’s to the NAT server’s. This change is recorded in the NAT mapping database along with the destination address. Once a reply is received from the internet server, NAT matches the reply’s source address to an address stored in its mapping database and then uses the linked client address to redirect the response packet to its intended destination. This process is known as stateful NAT because it maintains information about the communication sessions between clients and external systems.
Automatic Private IP Addressing
Automatic Private IP Addressing (APIPA), also known as link-local address assignment (defined in RFC 3927), assigns an IP address to a system in the event of a Dynamic Host Configuration Protocol (DHCP) assignment failure. APIPA is primarily a feature of Windows, since no other OS has adopted the standard. APIPA assigns each failed DHCP client an IP address from the range of 169.254.0.1 to 169.254.255.254 along with the default