Software Security Design Principles

Software Security Design Principles

Least Privilege

• Granting only the minimum privileges and access required for a user or system to perform their tasks
• Reducing the attack surface by limiting the potential damage that can be done
• Examples:
  • Running a process with a non-administrative account
  • Restricting access to sensitive data and resources

Defense In Depth

• Implementing multiple layers of security controls to protect against different types of attacks
• Providing redundancy and backup systems in case one layer is compromised
• Examples:
  • Firewalls, intrusion detection systems, and encryption
  • Implementing both username/password authentication and two-factor authentication

Separation Of Concerns

• Dividing a system into separate components, each handling a specific task or function
• Reducing the complexity and potential vulnerabilities of a single component
• Examples:
  • Separating authentication and authorization logic
  • Using microservices architecture to separate functionality

Fail-Safe Defaults

• Designing systems to default to a secure state in the event of a failure
• Ensuring that the system fails in a way that prevents unauthorized access or data breaches
• Examples:
  • Automatically logging out users after a period of inactivity
  • Defaulting to a secure configuration in the event of a system failure

Economy Of Mechanism

• Minimizing the complexity of security mechanisms to reduce the potential for errors and vulnerabilities
• Using simple, well-tested, and widely-used security mechanisms
• Examples:
  • Using established encryption algorithms instead of custom implementations
  • Implementing a simple, role-based access control system

Principle of Weakest Link

• Recognizing that a system is only as secure as its weakest component
• Focusing on securing the most vulnerable components first
• Examples:
  • Identifying and prioritizing the most critical vulnerabilities to patch
  • Implementing additional security measures to protect sensitive data

Authentication and Authorization

• Authentication: verifying the identity of a user or system
• Authorization: determining what actions a user or system is allowed to perform
• Examples:
  • Using username/password authentication and role-based access control
  • Implementing multi-factor authentication and attribute-based access control

Software Security Design Principles

Least Privilege

• Grants minimum privileges and access required for a user or system to perform tasks
• Reduces attack surface by limiting potential damage
• Examples: running processes with non-admin accounts, restricting access to sensitive data and resources

Defense In Depth

• Implements multiple layers of security controls to protect against different types of attacks
• Provides redundancy and backup systems in case one layer is compromised
• Examples: firewalls, intrusion detection systems, encryption, username/password and two-factor authentication

Separation Of Concerns

• Divides a system into separate components, each handling a specific task or function
• Reduces complexity and potential vulnerabilities of a single component
• Examples: separating authentication and authorization logic, using microservices architecture

Fail-Safe Defaults

• Designs systems to default to a secure state in the event of a failure
• Ensures that the system fails in a way that prevents unauthorized access or data breaches
• Examples: automatically logging out users after inactivity, defaulting to secure configuration in system failure

Economy Of Mechanism

• Minimizes complexity of security mechanisms to reduce errors and vulnerabilities
• Uses simple, well-tested, and widely-used security mechanisms
• Examples: using established encryption algorithms, implementing simple role-based access control

Principle of Weakest Link

• Recognizes that a system is only as secure as its weakest component
• Focuses on securing the most vulnerable components first
• Examples: identifying and prioritizing critical vulnerabilities, implementing additional security measures for sensitive data

Authentication and Authorization

• Authentication: verifies the identity of a user or system
• Authorization: determines what actions a user or system is allowed to perform
• Examples: username/password authentication and role-based access control, multi-factor authentication and attribute-based access control