問題一覧
1
A security analyst decrypted a data set with the same key that originally encrypted the data set. Which cryptographic operation did the analyst use?
SYMMETRIC
2
Which cipher uses a grid to map letters into numeric values?
BIFID
3
A security analyst is validating the integrity and authenticity of a data transaction. Which PKI component is being used?
DIGITAL SIGNATURE
4
Which attack tries every combination of letters, numbers, and special characters?
BRUTE-FORCE
5
Which certificate management process involves key recovery?
ISSUED
6
Why should an asymmetric public key be used to encrypt a symmetric key that is being sent to one person?
It encrypts a small amount of information, which is decrypted with the corresponding private key.
7
How does TKIP improve WPA over WEP?
Hashes the initialization vector and secret key
8
How many transformation rounds does AES use with a 128-bit key?
10
9
How is information about Bitcoin transactions stored?
Distributed peer-to-peer network
10
What should an administrator use to import and export all items written using X.509 that are part of a chain of trust?
Public Key Cryptography Standard (PKCS) #12
11
What is the length (in bits) of the private key used to sign transactions and associated with an individual wallet in the context of Bitcoin?
256
12
What is an example of a symmetric algorithm?
AES
13
How does cipher block chaining (CBC) create randomness in a second block after encrypting the first block with an initialization vector (IV)?
Uses the results of the IV to encrypt the next block
14
Which encryption mode always produces the same result for the same plaintext?
ECB
15
Which symmetric encryption technique uses a 56-bit key size and a 64-bit block size?
DES
16
What is the length (in bits) of an MD5 hash output?
128
17
What is a difference between WPA-Enterprise and WPA-Personal?
Support for an authentication server
18
Which field displays the hash, or digest, of the certificate in an X.509 certificate?
Thumbprint
19
What can XOR use as a pseudorandom number to create unique ciphertext?
Initialization vector
20
What is one of the primary characteristics of a blockchain in the context of Bitcoin?
Transactions between each block are chained.
21
Which technique should a security analyst use to determine the key length in a Vigenère cipher?
Kasiski examination
22
Which information protection method has an 80-bit key and operates on 64-bit data blocks?
SKIPJACK
23
Which mechanism can be used to ensure perfect forward secrecy during key exchange when using symmetric encryption?
ECDH
24
Which task does a root CA perform before publishing its own certificate?
Signing it with its private key
25
Which two components involved in performing encryption are known to the party that will perform decryption before symmetric encryption is applied? Choose 2 answers.
Cryptographic algorithm, Cryptographic key
26
Which symmetric encryption technique uses a 56-bit key size and a 64-bit block size?
WPA
27
Which mechanism mitigates a copy-and-paste attack when using AES?
Output feedback (OFB) loop
28
Which encryption algorithm did the National Institute of Standards and Technology (NIST) designate as a specification for the encryption of electronic information?
AES
29
How does CBC mode encryption function?
Uses an initialization vector (IV) to encrypt the first block, then uses the result of the encryption to encrypt the next block
30
Which cipher uses a five-by-five matrix with nonrepeating characters?
PLAYFAIR
31
Which type of cipher is ChaCha?
Stream
32
What is the maximum length (in bits) of encryption keys used by the WEP protocol?
40
33
Which default port must be open for the IPsec key exchange to be successful?
UDP 500
34
Which mode of block encryption results in the same outcome for matching blocks of a plaintext message?
ELECTRONIC CODE BOOK (ECB)
35
What does a frequency analysis attack to break encryption involve?
Analyzing ciphertext to identify text variation and comparing the text to standard English characters
36
Which algorithm is used to generate the thumbprint of a certificate?
SHA-1
37
What is the key size for RC4 with WEP?
40 bits
38
How does a dictionary attack break a cipher?
Takes a list of the most common words and tries each entry
39
Which encryption component ensures that the compromise of a long-term key prevents the compromise of any previous session keys?
FORWARD SECRECY
40
What is the role of a key in asymmetric encryption and decryption?
A public key is used for encryption, and a private key is used for decryption.
41
Which PKI component generates digital certificates?
Certificate authority (CA)
42
How many transformation rounds does AES use with a 192-bit key?
12
43
What should be used when large amounts of data need to be encrypted and decrypted for secure storage based on groupings of 128, 192, or 256 bits?
SYMMETRIC BLOCK
44
What will a Layer 2 switch do when the destination MAC address of a received frame is not in the MAC table?
It forwards the frame out of all ports except for the port at which the frame was received.
45
Which mode encrypts each group with the same key, leaving each group independent of the others?
ECB
46
How many characters are used in an LM hash password?
14
47
Which protocol indicates the virtual private network (VPN) is using Authentication Header (AH)?
51
48
A Windows credential is identified as follows: user:FDA95FBABC199D22LLD3B435B51876KK:199DDFD4EF0E9CD9KMNC6FE771IL124B8::: What is used to store this password?
NTLM
49
Large volumes of plaintext need to be encrypted, and the encryption keys need to be securely distributed. Which approach should be used for encryption and distribution?
Encrypt by using symmetric keys and distribute by using asymmetric keys
50
What are two features of ARP? (Choose two.)
If a host is ready to send a packet to a local destination device and it has the IP address but not the MAC address of the destination, it generates an ARP broadcast. , If a device receiving an ARP request has the destination IPv4 address, it responds with an ARP reply.
51
Which cipher is used with WEP?
RC4