Web Development Security 4

Question 1

What is a timing attack in the context of web authentication?

Accepted Answer

Exploiting measurable differences in response time to infer whether a guess (e.g., password or token) is partially correct

Answer

Timing attacks measure response latency variations (e.g., early exit on string comparison) to deduce secret values one character at a time.

Question 2

Which of the following best describes a stored (persistent) XSS attack?

Accepted Answer

Malicious script is saved in the server's database and served to all users who view the affected page

Answer

Stored XSS persists in the database (e.g., a comment field) and executes in every victim's browser when they load the page containing the payload.

Question 3

What does HSTS (HTTP Strict Transport Security) accomplish?

Accepted Answer

It instructs browsers to only connect to the site over HTTPS for a specified duration, preventing protocol downgrade attacks

Answer

HSTS uses the Strict-Transport-Security response header to tell browsers to refuse HTTP connections to the domain for the max-age period.

Question 4

An API returns a list of orders and uses sequential numeric IDs in the URL (e.g., /api/orders/1001). What vulnerability does this expose?

Accepted Answer

Insecure Direct Object Reference (IDOR), allowing users to access other users' orders by changing the ID

Answer

IDOR occurs when predictable object references are not access-controlled, letting attackers enumerate and access unauthorized resources.

Question 5

Which hashing algorithm is currently recommended for securely storing passwords?

Accepted Answer

bcrypt, scrypt, or Argon2

Answer

bcrypt, scrypt, and Argon2 are adaptive, memory-hard algorithms designed to be slow and costly to brute-force, unlike general-purpose hashes.

Web Development Practice Test