Wireless, Cryptography & Cloud

To crack a WPA2-PSK network offline, an attacker first needs to capture which piece of information by deauthenticating a client and waiting for it to reconnect?

• A The ISP account password
• B The DHCP lease table
• C The router's serial number
• D The 4-way handshake ✓

Answer: Capturing the WPA2 4-way handshake lets an attacker perform an offline dictionary or brute-force attack against the pre-shared key, commonly forcing it by sending deauthentication frames.

Which statement correctly describes the difference between symmetric and asymmetric encryption?

• A Symmetric uses one shared key for encryption and decryption; asymmetric uses a public/private key pair ✓
• B Symmetric is always slower than asymmetric encryption
• C Asymmetric encryption uses the same key for both parties
• D Symmetric encryption cannot be used for bulk data

Answer: Symmetric encryption (e.g., AES) uses a single shared secret key for both encryption and decryption, whereas asymmetric encryption (e.g., RSA) uses a mathematically linked public and private key pair.

What primary security property does a cryptographic hash function such as SHA-256 provide?

• A Availability, by compressing files for faster transfer
• B Non-repudiation, by exchanging session keys
• C Confidentiality, by encrypting data so it can later be decrypted
• D Integrity, by producing a fixed-length one-way digest that changes if the input changes ✓

Answer: A cryptographic hash is a one-way function producing a fixed-length digest; any change to the input changes the output, making hashes ideal for verifying data integrity (they are not reversible like encryption).

A company stores files in a cloud object-storage bucket (e.g., Amazon S3) that is left publicly readable. What is the most direct consequence?

• A Anyone on the internet can list and download the stored data ✓
• B The cloud provider blocks all access by default
• C The data is replicated only to the owner's laptop
• D The bucket automatically encrypts itself

Answer: A misconfigured publicly readable object-storage bucket exposes its contents so anyone who finds the URL can enumerate and download the data, a leading cause of cloud data breaches.

Under the cloud shared-responsibility model for Infrastructure-as-a-Service (IaaS), which task is the CUSTOMER responsible for rather than the provider?

• A Powering and cooling the servers
• B Securing the physical data-centre hardware
• C Patching the guest operating system and applications they deploy ✓
• D Maintaining the hypervisor

Answer: In the IaaS shared-responsibility model the provider secures the underlying physical and virtualization layers, while the customer is responsible for the guest OS, applications, and their data and configurations.

Which wireless security protocol is considered insecure because its use of RC4 with weak initialization vectors allows the key to be recovered using tools like Aircrack-ng?

• A WPA3-SAE
• B WEP ✓
• C WPA2-Enterprise
• D EAP-TLS

Answer: WEP relies on RC4 with short, reusable initialization vectors that leak key material; capturing enough IVs lets tools such as Aircrack-ng recover the key, so WEP is deprecated.