Secure Software Architecture

Explain the limitations of solely relying on Static Application Security Testing (SAST) for identifying vulnerabilities in a highly polymorphic and obfuscated codebase, particularly in scenarios where runtime behavior significantly deviates from static analysis.

Describe the challenges associated with implementing a hybrid security model that integrates both SAST and DAST, including strategies for resolving conflicting vulnerability reports and minimizing redundancy in testing efforts.

What would be the effect on security posture of using a DAST tool against a system that implements aggressive rate limiting and account lockout policies?

Suppose you discover a Cross-Site Scripting (XSS) vulnerability in a legacy application. Explain the trade-offs between applying contextual output encoding versus implementing a Content Security Policy (CSP) to mitigate the risk.

Explain the implications of using a reverse proxy with inadequate input validation, focusing on how an attacker might exploit this setup to bypass security controls on the backend servers.

Discuss the challenges in applying traditional penetration testing methodologies to serverless architectures, emphasizing the need for novel approaches to assess function-level vulnerabilities and inter-function communication.

Describe the limitations of signature-based intrusion detection systems (IDS) in detecting sophisticated cyber attacks that utilize advanced evasion techniques such as steganography and polymorphic code.

Explain the concept of 'data residency' in the context of cloud computing and discuss the legal and technical challenges in ensuring compliance with data residency requirements across multiple jurisdictions.

Discuss the security implications of using third-party APIs in a microservices architecture, focusing on the challenges of managing trust relationships and mitigating the risk of supply chain attacks.

What advanced strategies would an organization employ to mitigate advanced persistent threats (APTs) that have already breached the initial perimeter security, emphasizing lateral movement detection and data exfiltration prevention?

In a zero-trust network architecture, how can you implement and verify continuous authentication and authorization for users and devices, especially when accessing highly sensitive data or critical systems?

Explain the limitations of traditional signature-based Web Application Firewalls (WAFs) in protecting against zero-day exploits and how machine learning-based WAFs can overcome these limitations. What are the drawbacks of a machine learning approach?

Imagine you are designing a system to protect against SQL injection. Detail a methodology to combine parameterized queries, least privilege accounts, and input validation in a secure manner.

Outline advanced techniques to prevent Cross-Site Request Forgery (CSRF) attacks in Single Page Applications (SPAs) that rely heavily on JavaScript and APIs beyond the typical use of synchronizer tokens.

How should an organization design a comprehensive API security strategy that incorporates mutual TLS (mTLS), OAuth 2.0 with PKCE, and API gateways to create a multi-layered defense against unauthorized access and API abuse?

Evaluate the effectiveness of using address space layout randomization (ASLR) as a standalone security measure against memory corruption vulnerabilities, particularly against advanced exploitation techniques like return-oriented programming (ROP).

Elaborate on the complexities of ensuring data integrity in a distributed database system, considering the CAP theorem and the trade-offs between consistency, availability, and partition tolerance.

When creating code for a secure system, when is it advisable or inadvisable to build your own cryptography?

What are the most current advances in homomorphic encryption, and what do they allow us to do that would not have been practical 10 years ago?

Outline a strategy for implementing secure multi-party computation (MPC) in a financial transaction system that involves multiple banks, focusing on techniques to prevent collusion and ensure data privacy.

Explain the concept of 'security by obscurity' and detail scenarios where it might provide a false sense of security. How would you advocate for its complete removal?

What modern memory protection schemes offer the best security guarantees and why, versus the security schemes offered 10 years ago?

Describe the challenges in implementing secure boot on embedded systems with limited resources and diverse hardware architectures, focusing on techniques to verify the integrity of the bootloader and operating system.

Explain the trade-offs between using full disk encryption (FDE) versus file-level encryption in terms of performance, security, and manageability across a large enterprise environment.

Outline a comprehensive strategy for managing and mitigating the risks associated with shadow IT, including techniques for discovering unauthorized devices and applications, enforcing security policies, and educating users.

Describe the steps involved in conducting a thorough security audit of a complex cloud infrastructure, including techniques for assessing compliance with industry regulations and identifying potential misconfigurations.

How best to prevent race conditions from occurring in a multi-threaded or asynchronous application?

How does the concept of 'defense in depth' apply to secure software architecture. Provide an example.

Discuss the challenges and solutions associated with securely managing cryptographic keys in a distributed microservices architecture, especially when dealing with frequent key rotation and diverse key types.

Explain the concept of 'federated identity management' and describe its benefits and challenges in enabling secure access to resources across multiple organizations, focusing on trust establishment and interoperability.

Describe the key differences between the AES, ChaCha20, and Serpent ciphers with respect to their security properties, performance characteristics, and suitability for different use cases.

A highly skilled penetration tester has discovered the ability to upload arbitrary files to a sensitive web server. Describe an advanced strategy for preventing code execution, including specific security controls to evade.

How do you perform data sanitization to prevent code injection in a system that accepts both Markdown and raw HTML input.

Outline an advanced strategy for protecting against denial-of-service (DoS) attacks in a cloud environment, including techniques for detecting malicious traffic, mitigating attacks, and ensuring service availability.

What class of attack can input validation schemes be most easily bypassed, and how do you advise someone to prevent that?

Explain the security benefits of system call filtering in sandboxing architectures. What attacks does it prevent?

Describe the challenges associated with implementing confidential computing techniques, such as Intel SGX, in a multi-tenant cloud environment. What attack mitigations are provided by an enclaved system?

What are the current weaknesses of the TLS protocol and how are they being addressed in the newest version?

In what situation might it be preferable to use blockchain cryptography over public-key cryptography?

How would you audit the use of a serverless system to know what data ingress and egress is occurring, and that no unintended access of data occurs?