CSLLP Secure Software Design 2 — Questions and Answers
Question 1: What is the purpose of an interface design review in secure software development?
- To evaluate user experience design
- To identify trust boundaries and validate that security controls are applied at all interfaces (Correct answer)
- To review API performance characteristics
- To assess database schema design
Correct answer: To identify trust boundaries and validate that security controls are applied at all interfaces
Interface design reviews examine all points where data crosses trust boundaries to ensure input validation, authentication, and authorization controls are correctly applied.
Question 2: Which cryptographic algorithm is currently recommended by NIST for symmetric encryption?
- DES
- 3DES
- RC4
- AES (Correct answer)
Correct answer: AES
NIST recommends AES (Advanced Encryption Standard) for symmetric encryption, with 128-bit, 192-bit, or 256-bit key lengths depending on the security requirement.
Question 3: What security design pattern ensures that a user must provide evidence from at least two distinct authentication factors?
- Single sign-on (SSO)
- Multi-factor authentication (MFA) (Correct answer)
- Role-based access control (RBAC)
- Attribute-based access control (ABAC)
Correct answer: Multi-factor authentication (MFA)
MFA requires users to present at least two factors from different categories (something you know, something you have, something you are) before granting access.
Question 4: Which design approach assigns permissions based on a user's organizational role rather than their individual identity?
- Discretionary access control (DAC)
- Mandatory access control (MAC)
- Role-based access control (RBAC) (Correct answer)
- Attribute-based access control (ABAC)
Correct answer: Role-based access control (RBAC)
RBAC assigns permissions to roles (such as admin, editor, viewer) and then assigns roles to users, simplifying permission management in large organizations.
Question 5: What is the purpose of a certificate authority (CA) in a public key infrastructure (PKI)?
- To generate symmetric encryption keys for users
- To issue and sign digital certificates that bind public keys to identities (Correct answer)
- To store private keys securely on behalf of users
- To perform key exchange during TLS handshakes
Correct answer: To issue and sign digital certificates that bind public keys to identities
A CA is a trusted entity that verifies the identity of certificate requestors and issues digitally signed certificates binding a public key to an identity.
Question 6: Which threat modeling methodology focuses on assets, attack surfaces, and mitigations and was developed by Microsoft?
- PASTA
- OCTAVE
- STRIDE (Correct answer)
- VAST
Correct answer: STRIDE
STRIDE (Spoofing, Tampering, Repudiation, Information disclosure, Denial of service, Elevation of privilege) is Microsoft's threat categorization framework used with data flow diagrams.
CSLLP Secure Software Design 2
What is the purpose of an interface design review in secure software development?