Cryptography Concepts EHE Practice Questions (Page 8)

Questions 36–39

1. 36application · medium

   A web developer is designing a login system. They want to store user passwords in a database so that even if the database is breached, the passwords cannot be easily recovered. Which approach is the most secure?

   • AStore the passwords in plain text but restrict database access.
   • BStore the MD5 hash of each password without a salt.
   • CStore a salted hash of each password using a strong hash function like bcrypt.
   • DEncrypt the passwords with AES using a hardcoded key in the application code.
   Reveal Solution Discussion Select an answer first
2. 37application · medium

   A software company distributes a firmware update to customers. The update file is large, and the company wants customers to verify that the file was not corrupted or tampered with during download. The company also wants to confirm that the update genuinely came from them. Which combination should they provide to customers?

   • AA cryptographic hash of the file and a digital signature of that hash using the company's private key.
   • BA hash of the file encrypted with the customer's public key.
   • CA simple checksum like CRC32 of the file.
   • DAn encrypted copy of the file using the company's public key.
   Reveal Solution Discussion Select an answer first
4. 38expert · hard

   A security analyst is investigating a brute-force attack on an encrypted file. The attacker is trying all possible keys. The analyst wants to slow down the attack. Which control is most effective?

   • AUse a stronger hash algorithm for the file.
   • BRotate the encryption key every hour.
   • CUse a longer encryption key, such as AES-256 instead of AES-128.
   • DCompress the file before encryption.
   Reveal Solution Discussion Select an answer first
5. 39foundation · easy

   Which type of cryptographic attack involves trying every possible key until the correct one is found?

   • AMan-in-the-middle attack
   • BSide-channel attack
   • CKnown-plaintext attack
   • DBrute force attack
   Reveal Solution Discussion Select an answer first