security-design.md

Security Design Principles

References:

• https://cheatsheetseries.owasp.org/cheatsheets/Secure_Product_Design_Cheat_Sheet.html
• https://www.redhat.com/en/blog/security-design-security-principles-and-threat-modeling

Least Privilege

• Minimum access required to perform function
• Limit unauthorized access to resources
• Example: do not run applications as root user
• Example: use time-to-live access to limit control to a given time period

Full Disclosure of Vulnerabilities

• Ensure that the window of vulnerability is kept as short as possible when bugs are discovered

Automated Theorem Proving

• Prove correctnes of critical software

Code Review + Unit Testing

• Attempt security for modules where formal correctness proofs are not possible

Sepration of Duties

• Also known as: Sepration of Concerns
• System of checks and balances to ensure no individual has control over all aspects
• Assign different tasks to different people, to ensure that a single person does not control the entire process
• Reduce fraud
• Example: a business expense should be submitted and approved by different people

Defense in Depth

• Layers of security control to protect access
• Force attacker to defeat multiple layers and avoid single point of failure
• Example: multi-factor authentication for user login

Zero Trust

• All users, devices, and networks are untrusted, and must be verified
• Example: do not assume an email was written by a colleague unless it has been verified

Security in the Open

• Emphasizes the importance of security in open source software
• Developers should be aware of security implications of their software and ensure code is secure
• Example: use dependency scanning to analyze software

Secure by Default

• Deny access by default
• Requires deliberate, conscience decision in order to be made insecure
• Example: a web server configuration should default to HTTPS

Audit Trails

• Track system activity so when breach occurs the mechanism and extent can be determined
• Best practices: store remotely and append only logging
• Example: access logs

Minimize Attack Surface

• Example: remove unused code or features

Open Design

• Do not rely on secret designs, attacker ignorance or security by obscurity
• Invite and encourage open review and analysis

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Jargon

• eavesdropping
• privilege escalation
• side-channel attack
• backdoor
• reverse engineering
• tampering
• html smuggling - defeat content filters
• phising - attempt to acquire sensitive information such as username and password, credit card, etc, by deceiving users via email, fake website, social engineering, etc.
• cross-site request forgery
  • one-click attack
  • exploits a trusted user to perform action
  • sites that rely on identity (but not verification)
  • exploits trust in user
• stack overflow
• denial of service attack
• cross-site scripting
  • exploits a web form that accepts user input that is not sanitized for JavaScript
  • runs code on any web brwoser that loads the page including logged-in users
• SQL injection - exploits code that lacks validation and uses sql query to access database with original user data
• man-in-the-middle
• social engineering
• penetration testing
• zero-day exploit
• spoofing - identify as another person or system by falsifying data
• malware
• trojan horse