MEAN MEAN Stack Security and Deployment

Question 1

What is JWT (JSON Web Token) and how is it used for authentication in a MEAN stack?

Accepted Answer

A self-contained token encoding user claims that Angular sends in Authorization headers for Express to verify

Answer

JWT is a signed, base64-encoded token containing user claims; Angular stores it (localStorage/memory) and sends it in Authorization: Bearer headers, which Express validates with the secret key.

Question 2

What is bcrypt used for in a Node.js Express application?

Accepted Answer

Hashing passwords with a salt before storing in MongoDB to protect against rainbow table attacks

Answer

bcrypt hashes passwords with a random salt and configurable cost factor, making brute-force and rainbow table attacks computationally expensive even if the database is compromised.

Question 3

What is Cross-Site Scripting (XSS) and how does Angular protect against it?

Accepted Answer

Injecting malicious scripts into web pages; Angular auto-sanitizes all data bound to templates by treating it as text

Answer

XSS injects malicious scripts into pages viewed by other users; Angular's template engine treats all values as untrusted text by default, escaping HTML before rendering.

Question 4

What is CSRF (Cross-Site Request Forgery) and how is it mitigated in Express?

Accepted Answer

Tricks users into submitting requests they didn't intend; mitigated with CSRF tokens or SameSite cookies

Answer

CSRF attacks submit unauthorized requests using the victim's credentials; CSRF tokens embedded in forms or SameSite cookie attribute prevent cross-origin request forgery.

Question 5

What is NoSQL injection and how can it occur in a MongoDB/Express application?

Accepted Answer

Sending malicious operators like $where or $gt in request bodies to manipulate MongoDB queries

Answer

NoSQL injection occurs when unvalidated user input is passed directly to MongoDB queries, allowing attackers to inject operators like $where or $regex to bypass authentication.

MEAN - Stack Development Practice Test

MEAN - Stack Development Practice Test

MEAN MEAN Stack Security and Deployment