312-50v12 Free Practice Test

- (Exam Topic 1)
A bank stores and processes sensitive privacy information related to home loans. However, auditing has never been enabled on the system. What is the first step that the bank should take before enabling the audit feature?

1. A. Perform a vulnerability scan of the system.
2. B. Determine the impact of enabling the audit feature.
3. C. Perform a cost/benefit analysis of the audit feature.
4. D. Allocate funds for staffing of audit log review.

Correct Answer: B

- (Exam Topic 1)
Which mode of IPSec should you use to assure security and confidentiality of data within the same LAN?

1. A. ESP transport mode
2. B. ESP confidential
3. C. AH permiscuous
4. D. AH Tunnel mode

Correct Answer: A

- (Exam Topic 2)
What is one of the advantages of using both symmetric and asymmetric cryptography in SSL/TLS?

1. A. Symmetric algorithms such as AES provide a failsafe when asymmetric methods fail.
2. B. Asymmetric cryptography is computationally expensive in compariso
3. C. However, it is well-suited to securely negotiate keys for use with symmetric cryptography.
4. D. Symmetric encryption allows the server to securely transmit the session keys out-of-band.
5. E. Supporting both types of algorithms allows less-powerful devices such as mobile phones to use symmetric encryption instead.

Correct Answer: D

- (Exam Topic 2)
Which of the following commands checks for valid users on an SMTP server?

1. A. RCPT
2. B. CHK
3. C. VRFY
4. D. EXPN

Correct Answer: C
The VRFY commands enables SMTP clients to send an invitation to an SMTP server to verify that mail for a selected user name resides on the server. The VRFY command is defined in RFC 821.The server sends a response indicating whether the user is local or not, whether mail are going to be forwarded, and so on. A response of 250 indicates that the user name is local; a response of 251 indicates that the user name isn’t local, but the server can forward the message. The server response includes the mailbox name.

- (Exam Topic 1)
What is the known plaintext attack used against DES which gives the result that encrypting plaintext with one DES key followed by encrypting it with a second DES key is no more secure than using a single key?

1. A. Man-in-the-middle attack
2. B. Meet-in-the-middle attack
3. C. Replay attack
4. D. Traffic analysis attack

Correct Answer: B
https://en.wikipedia.org/wiki/Meet-in-the-middle_attack
The meet-in-the-middle attack (MITM), a known plaintext attack, is a generic space–time tradeoff cryptographic attack against encryption schemes that rely on performing multiple encryption operations in sequence. The MITM attack is the primary reason why Double DES is not used and why a Triple DES key (168-bit) can be bruteforced by an attacker with 256 space and 2112 operations.
The intruder has to know some parts of plaintext and their ciphertexts. Using meet-in-the-middle attacks it is possible to break ciphers, which have two or more secret keys for multiple encryption using the same algorithm. For example, the 3DES cipher works in this way. Meet-in-the-middle attack was first presented by Diffie and Hellman for cryptanalysis of DES algorithm.