Over the past few decades, there have been tens of thousands of successful malicious software security attacks. These include a data attack that affected approximately 40 million Target customers, the Facebook-Cambridge Analytica scandal in 2018, which involved unauthorized access to user data through a third-party app’s API, and an XSS scripting attack that, within 20 hours, infected over one million Myspace profiles.

Hundreds of thousands of unintended user mistakes are due to poorly designed or implemented software. These mistakes often go unreported, even though the software or experiment may fail, or humans are harmed. Some examples include NASA’s Mars Climate Orbiter, where the spacecraft’s navigation software used metric units, while ground control provided data in imperial units. This mismatch resulted in incorrect calculations, causing the orbiter to approach Mars at too low an altitude, ultimately leading to its failure. Another...

Software security principles are fundamental guidelines and best practices that help design, develop, and maintain secure software systems. These principles aim to protect software applications and their data from a wide range of threats and vulnerabilities. Here are some fundamental software security principles:

• Least privilege: Give individuals or processes only the minimum access and permissions they need to perform their tasks. This principle reduces the potential for unauthorized access or abuse of privileges.
• Defense in depth: Implement multiple security controls and safeguards layers rather than relying solely on a single security measure. This approach helps to mitigate risks and reduce the impact of security breaches.
• Fail-safe defaults: Configure systems and applications to operate securely by default. Fail-safe defaults mean that if a configuration or access control is not explicitly defined, it should be denied or disabled.
• Input validation...

When considering software security principles, you must reference Open Web Application Security Project (OWASP) terminology. OWASP is an online community and organization that focuses on web application security. OWASP is known for its extensive collection of resources and tools related to web application security, which are freely available to the public. The primary goal of OWASP is to improve software security by providing knowledge and tools that help organizations and individuals develop and maintain secure web applications.

Some of the critical activities and resources associated with OWASP include the following:

• Top 10: This is a regularly updated list of the top 10 most critical web application security risks. It serves as a guide for developers and organizations to prioritize their security efforts.
• Projects: OWASP sponsors and supports various open source projects related to web application security. These projects cover...

The National Institute of Standards and Technology (NIST) released various guidelines and frameworks for secure software development. One of the critical resources NIST provides is the NIST Secure Software Development Framework (SSDF), designed to help organizations enhance the security of their software development processes. Here’s an overview of the NIST SSDF:

• Secure software development guidelines: NIST’s SSDF provides guidance on secure software development practices. It covers many topics, including requirements analysis, design, coding, testing, deployment, and maintenance, with a strong focus on security.
• Secure software development principles: The framework promotes fundamental security principles and best practices to be integrated into every phase of the software development life cycle. These principles include secure coding, security testing, threat modeling, and secure software architecture.
...

MITRE Corporation is a not-for-profit organization that operates Federally Funded Research and Development Centers (FFRDCs) in the United States. One of MITRE’s key contributions to software security is the development and maintenance of the Common Weakness Enumeration (CWE) and Common Vulnerabilities and Exposures (CVE) standards:

1. CWE:

• Purpose: CWE is a community-developed dictionary of common software weaknesses that can lead to security vulnerabilities. It provides a standardized way to identify, describe, and categorize software weaknesses.
• Use cases: Developers, security professionals, and researchers use CWE to identify and mitigate vulnerabilities during the SDLC. It aids in improving the security of software by providing a common language for discussing and addressing weaknesses.

2. CVE:

• Purpose: CVE is a standardized identifier system for publicly known security vulnerabilities. Each CVE entry includes a unique identifier...

SDLCs are systematic processes or methodologies that software development teams use to plan, design, build, test, deploy, and maintain software applications. These life cycles help ensure that software projects are completed efficiently, on time, and within budget while meeting the specified requirements and maintaining high quality. There are several different SDLC models, and the choice of which one to use depends on the project’s needs and requirements. Here are some of the most common SDLC models:

• Waterfall model: The Waterfall model is a sequential set of steps involved in software development. It divides the project into distinct phases: requirements, design, implementation, testing, deployment, and maintenance. Each phase must be completed before the next one begins, and it is challenging to make changes after a phase is complete. It is well-suited for projects with well-defined requirements that are unlikely to change.
• Agile...

The Microsoft Security Development Lifecycle (SDL) is a set of practices and guidelines that Microsoft has developed and implemented to improve the security of its software products. The SDL is designed to ensure that security is integral to the software development process from the beginning. It includes a set of best practices, tools, and processes that help identify and address security vulnerabilities at all stages of software development. Here are some critical aspects of the Microsoft SDL:

• Training and education: The SDL emphasizes training and education for developers and other stakeholders to raise awareness of security issues and best practices. The training includes secure coding training and security awareness programs.
• Threat modeling: One of the critical elements of the SDL is threat modeling, which involves identifying potential threats and vulnerabilities in the design and architecture of the software. By...

CIA is an acronym representing the core principles of information security: confidentiality, integrity, and availability. These principles are fundamental to designing and implementing secure systems and are often called the CIA triad:

• Confidentiality ensures that information is only accessible to those with authorized permissions. Software security involves encryption, access controls, and user authentication to protect sensitive data from unauthorized access.
• Integrity ensures that information remains accurate and unaltered during storage, processing, or transmission. In software security, techniques such as data validation, checksums, digital signatures, and version control are used to maintain data and software integrity.
• Availability ensures that information and resources are available and accessible when needed. Software security involves measures to prevent and mitigate disruptions, such as redundancy, failover systems...

This chapter introduced secure software development principles. We looked at some organizations supporting the secure software development process, including OWASP and NIST. We also discussed the standard principles recognized by most secure developers. Next, we examined differences in different software development models and realized that the methodology presented in this book will work with all the different life cycles, independent of which are used. Lastly, we explored the Microsoft SDL and compared the approach presented in this book.

In the next chapter, we will look at building a more extensive example project based on what we have learned.

1. What is the primary purpose of the “fail securely” principle?
   1. To avoid using third-party libraries
   2. To ensure that the application never experiences failures
   3. To immediately shut down the application in case of any issue
   4. To gracefully handle failures while maintaining security measures
2. What does the “divide and conquer” principle in secure design suggest?
   1. Security measures should be concentrated in a single layer for easier management
   2. Security tasks should be assigned to separate teams for better efficiency
   3. Complex problems should be divided into smaller, manageable components
   4. The application’s features should be divided between different development teams
3. Why does the principle of “minimize attack surface” suggest that applications should have fewer exposed entry points?
   1. To reduce the potential points of vulnerability and attack
   2. To increase the application’s processing speed
   3. To enhance the...

1. D
2. C
3. A
4. B
5. D
6. D
7. D
8. B
9. C
10. D