1.
Which of the following refers to the ability to be reasonably certain that data is not modified or tampered with:
Correct Answer
B. Integrity
Explanation
Integrity refers to the ability to be reasonably certain that data is not modified or tampered with. This means that the data remains intact, consistent, and accurate throughout its lifecycle. Maintaining data integrity is crucial for ensuring the reliability and trustworthiness of information. By implementing measures such as data encryption, checksums, and access controls, organizations can protect against unauthorized modifications or alterations to their data.
2.
Which of the following types of cryptography is typically used to provide an integrity check?
Correct Answer
D. Hash
Explanation
Hash cryptography is typically used to provide an integrity check. Hash functions take an input (message), perform a mathematical operation on it, and produce a fixed-size output (hash value). This hash value is unique to the input, so any change in the input will result in a different hash value. By comparing the hash value before and after transmission or storage, one can ensure that the data has not been tampered with. Therefore, hash cryptography is commonly used to verify the integrity of data.
3.
Which of the following describes the validation of a message’s origin?
Correct Answer
D. Non-repudiation
Explanation
Non-repudiation refers to the ability to ensure that a sender of a message cannot deny having sent the message. It provides evidence that the message originated from a specific sender and cannot be disputed. This is important in ensuring the integrity and authenticity of messages, as it prevents the sender from later denying their involvement or responsibility for the message.
4.
Identify the service provided by message authentication code (MAC) hash:
Correct Answer
A. Integrity
Explanation
A message authentication code (MAC) hash provides integrity to the data. It ensures that the data has not been tampered with during transmission or storage. By generating a unique hash value for the data, the MAC can verify its integrity by comparing the received hash value with the computed hash value. If they match, it means the data has not been altered. This helps to ensure the authenticity and reliability of the data.
5.
Which of the following provides the MOST secure form of encryption?
Correct Answer
C. AES
Explanation
AES (Advanced Encryption Standard) is considered the most secure form of encryption among the options provided. It is a symmetric encryption algorithm that uses a fixed block size of 128 bits and key sizes of 128, 192, or 256 bits. AES has been extensively studied and tested by experts in the field of cryptography and is widely used by governments, organizations, and individuals to protect sensitive data. It is resistant to various attacks and provides a high level of security, making it the preferred choice for encryption in many applications.
6.
Which of the following would be needed to ensure that a user who has received an email cannot claim that the email was not received?
Correct Answer
A. Non-repudiation
Explanation
Non-repudiation is the concept that ensures that a user who has received an email cannot deny receiving it. It provides evidence that the email was indeed delivered to the user and prevents them from falsely claiming that they did not receive it. Non-repudiation is achieved through various methods such as digital signatures and timestamps, which can be used to verify the authenticity and integrity of the email. This helps in establishing trust and accountability in electronic communications.
7.
A security specialist has downloaded a free security software tool from a trusted industry site. The source has published the MD5 hash values for the executable program. The specialist performs a successful virus scan on the download but the MD5 hash is different. Which of the following steps should the specialist take?
Correct Answer
A. Avoid executing the file and contact the source website administrator
Explanation
The specialist should avoid executing the file and contact the source website administrator. The fact that the MD5 hash is different suggests that the downloaded file may have been tampered with or corrupted. By contacting the source website administrator, the specialist can verify the integrity of the file and ensure that it is safe to use. It is important to exercise caution when downloading software, even from trusted sources, as there is always a risk of malicious activity.
8.
Encryption is the conversion of data into a form, called a ciphertext, that cannot be easily understood by unauthorized people. Which of he following is considered the weakest encryption?
Correct Answer
D. DES
Explanation
DES (Data Encryption Standard) is considered the weakest encryption out of the given options. DES uses a 56-bit key, which is relatively short compared to modern encryption standards. This makes it vulnerable to brute-force attacks, where an attacker tries all possible keys until finding the correct one. Additionally, DES has been around for a long time and has been extensively studied, leading to the discovery of various vulnerabilities and weaknesses. As a result, it is no longer considered secure for most applications and has been replaced by stronger encryption algorithms like AES.
9.
Which option is correct about a hash algorithms ability to avoid the same output from two guessed inputs?
Correct Answer
C. Collision resistance
Explanation
Collision resistance refers to the ability of a hash algorithm to prevent the occurrence of the same output for two different guessed inputs. In other words, it ensures that it is computationally infeasible to find two different inputs that produce the same hash value. This property is crucial in cryptographic applications as it helps to maintain the integrity and security of the data being hashed.
10.
Which description is true about how to accomplish steganography in graphic files?
Correct Answer
D. Replacing the least significant bit of each byte
Explanation
Steganography in graphic files involves hiding information within the file without being noticeable. The least significant bit (LSB) refers to the rightmost bit in a binary number. By replacing the LSB of each byte in a graphic file, it is possible to hide information without significantly altering the appearance of the file. This method is commonly used in steganography techniques to embed secret messages or data within graphic files.
11.
Which item will effectively allow for fast, highly secure encryption of a USB flash drive?
Correct Answer
C. AES256
Explanation
AES256 is the correct answer because it is a symmetric encryption algorithm that provides a high level of security and is widely used for encrypting data. It uses a 256-bit key length, which makes it extremely difficult to crack. AES256 is also known for its speed and efficiency, making it an effective choice for encrypting a USB flash drive quickly and securely. SHA-1, 3DES, and MD5 are not suitable options for fast and highly secure encryption of a USB flash drive.
12.
Which description is correct concerning the process of comparing cryptographic hash functions of system executables, configuration files, and log files?
Correct Answer
C. File integrity auditing
Explanation
File integrity auditing is the correct description concerning the process of comparing cryptographic hash functions of system executables, configuration files, and log files. This process involves generating a hash value for each file and comparing it to a known, trusted value. If the hash values match, it indicates that the file has not been altered or tampered with. This is commonly used in security systems to detect unauthorized changes to files, ensuring the integrity and security of the system.
13.
Encryption is the conversion of data into a form, called a ciphertext that cannot be easily understood by unauthorized people. Which encryption is the strongest by use of mathematical evaluation techniques?
Correct Answer
B. AES
Explanation
AES (Advanced Encryption Standard) is the strongest encryption method among the options provided. It is considered secure and widely used for protecting sensitive data. AES uses a symmetric key algorithm, which means that the same key is used for both encryption and decryption. It has undergone extensive mathematical evaluation and has been approved by the National Institute of Standards and Technology (NIST) for use in encrypting classified information.
14.
Which algorithms can best encrypt large amounts of data?
Correct Answer
A. Symmetric key algorithms
Explanation
Symmetric key algorithms can best encrypt large amounts of data because they use the same key for both encryption and decryption. This means that they are faster and more efficient for encrypting and decrypting large volumes of data compared to asymmetric key algorithms, ECC algorithms, and hashing algorithms. Symmetric key algorithms are particularly suitable for scenarios where speed and performance are important, such as encrypting large files or transmitting data over a network.
15.
Which method will most effectively verify that a patch file downloaded from a third party has not been modified since the time that the original manufacturer released the patch?
Correct Answer
B. Compare the final MD5 hash with the original
Explanation
Comparing the final MD5 hash with the original is the most effective method to verify that a patch file downloaded from a third party has not been modified since the time the original manufacturer released the patch. MD5 is a cryptographic hash function that generates a unique hash value for a file. By comparing the final MD5 hash of the downloaded patch file with the original MD5 hash provided by the manufacturer, any changes or modifications made to the file can be detected. If the hashes match, it indicates that the file has not been tampered with.
16.
Which of the following would be MOST desirable when attacking encrypted data?
Correct Answer
A. Weak key
Explanation
A weak key would be the most desirable when attacking encrypted data because it would make it easier to decrypt the data. A weak key refers to a key that is easily guessable or has a limited number of possible combinations, making it vulnerable to brute force or other attacks. By exploiting a weak key, an attacker can potentially bypass the encryption and gain unauthorized access to the data.
17.
Most current encryption schemes are based on:
Correct Answer
D. Algorithms
Explanation
Most current encryption schemes are based on algorithms. Algorithms are step-by-step procedures or formulas used to solve a problem or perform a task. In the context of encryption, algorithms are used to transform plaintext data into ciphertext, making it unreadable to unauthorized individuals. These algorithms use mathematical operations and cryptographic techniques to ensure the confidentiality, integrity, and authenticity of the encrypted data. By using strong and well-tested algorithms, encryption schemes can provide a high level of security for sensitive information.
18.
The Diffie-Hellman encryption algorithm relies on which of the following?
Correct Answer
B. Key exchange
Explanation
The Diffie-Hellman encryption algorithm relies on key exchange. This algorithm allows two parties to establish a shared secret key over an insecure communication channel. The parties generate their own private keys and exchange public keys. Using a mathematical formula, they can then compute the same shared secret key without ever directly transmitting it. This shared key can be used for encryption and decryption of messages, ensuring secure communication between the two parties.
19.
Which of the following will permit an administrator to find weak passwords on the network?
Correct Answer
D. A rainbow table
Explanation
A rainbow table is a precomputed table of hash values for a large number of possible passwords. It allows an administrator to compare hashed passwords on the network with the values in the rainbow table to identify weak passwords. By comparing the hashes, the administrator can quickly identify passwords that have already been cracked and are therefore vulnerable. A hash function, network mapper, and password generator do not specifically aid in finding weak passwords on the network.
20.
What is steganography primarily used for?
Correct Answer
A. Hiding information
Explanation
Steganography is primarily used for hiding information. It is a technique of concealing secret data within an innocent-looking cover medium, such as an image or audio file, in order to prevent unauthorized access or detection. This allows the sender to transmit sensitive information without arousing suspicion or attracting attention. Steganography ensures that the hidden message remains confidential and only accessible to the intended recipient, making it a useful tool for covert communication and data security.
21.
Which encryption algorithms can be used to encrypt and decrypt data?
Correct Answer
C. RC5
Explanation
RC5 is a symmetric encryption algorithm that can be used to both encrypt and decrypt data. It is a block cipher that operates on fixed-size blocks of data and uses a variable-length key. RC5 is known for its simplicity and efficiency, making it a popular choice for encryption in various applications. It provides a high level of security and can be implemented in different block sizes and key sizes to meet specific requirements.
22.
Which of the following would allow an administrator to find weak passwords on the network?
Correct Answer
C. A rainbow table
Explanation
A rainbow table is a precomputed table of hashes that can be used to quickly crack password hashes. By comparing the hashes of passwords on the network to the values in the rainbow table, an administrator can easily identify weak passwords. This method is efficient because it eliminates the need to hash every possible password individually.
23.
Which of the following refers to the ability to be reasonably certain that data is not disclosed to unintended persons?
Correct Answer
B. Confidentiality
Explanation
Confidentiality refers to the ability to be reasonably certain that data is not disclosed to unintended persons. It ensures that sensitive information remains private and only accessible to authorized individuals. This can be achieved through various measures such as encryption, access controls, and secure storage.
24.
In order to encrypt credit card data, which will be the most secure algorithm with the least CPU utilization?
Correct Answer
D. AES
Explanation
AES (Advanced Encryption Standard) is the most secure algorithm among the given options for encrypting credit card data. It is widely used and recommended by security experts. AES provides a high level of security and has been extensively tested and proven to be resistant against various cryptographic attacks. Additionally, AES is efficient in terms of CPU utilization, making it a suitable choice for encrypting sensitive data without putting excessive strain on system resources.
25.
Hashing is the transformation of a string of characters into a fixed length value or key that represents the original string. Hashing is used to index and retrieve items in a database. Which description is correct when a hashing algorithm generates the same hash for two different messages?
Correct Answer
C. A collision occurred
Explanation
When a hashing algorithm generates the same hash for two different messages, it is referred to as a collision. This means that two different inputs have produced the same output hash value. Collisions can occur in hashing algorithms due to the finite number of possible hash values compared to the infinite number of possible input messages.
26.
Which of the following describes a type of algorithm that cannot be reversed in order to decode the data?
Correct Answer
D. One Way Function
Explanation
A one-way function is a type of algorithm that cannot be reversed in order to decode the data. Once the data is encrypted using a one-way function, it becomes extremely difficult, if not impossible, to retrieve the original data without the use of a decryption key. This makes one-way functions ideal for securely storing sensitive information, as it ensures that even if the encrypted data is compromised, it cannot be easily decrypted and accessed by unauthorized individuals.
27.
What may be happening when hashing two different files creates the same result?
Correct Answer
C. A collision
Explanation
When hashing two different files creates the same result, it is referred to as a collision. This means that two distinct inputs have produced the same output in the hash function. Collisions are a natural occurrence in hash functions due to the finite size of the output space compared to the potentially infinite input space. While hash functions aim to minimize collisions, they cannot entirely eliminate them. Therefore, it is expected that collisions will occur occasionally, especially when dealing with a large number of inputs.
28.
Which of the following encryption algorithms relies on the inability to factor large prime numbers?
Correct Answer
C. RSA
Explanation
RSA is an encryption algorithm that relies on the inability to factor large prime numbers. It uses a public key to encrypt data and a private key to decrypt it. The security of RSA is based on the fact that it is computationally difficult to factor large prime numbers, making it difficult to determine the private key from the public key. This property makes RSA a popular choice for secure communication and data encryption.
29.
Secret Key encryption is also known as:
Correct Answer
D. Symmetrical
Explanation
Symmetrical encryption, also known as secret key encryption, uses the same key for both the encryption and decryption processes. This means that the sender and receiver must have access to the same secret key in order to encrypt and decrypt the message. It is called "symmetrical" because the encryption and decryption processes are symmetric or identical.
30.
Non-repudiation is enforced by which of the following?
Correct Answer
A. Digital signatures
Explanation
Digital signatures enforce non-repudiation by providing a way to verify the authenticity and integrity of a digital document or message. A digital signature is created using the sender's private key and can be verified using the sender's public key. This ensures that the signature can only be generated by the sender and cannot be tampered with by anyone else. Therefore, digital signatures provide a strong mechanism for proving the identity of the sender and ensuring that they cannot deny sending a particular message or document.
31.
Which statement correctly describes the difference between a secure cipher and a secure hash?
Correct Answer
C. A cipHer can be reversed, a hash cannot
Explanation
A secure cipher can be reversed, meaning that the original message can be recovered from the encrypted message using the decryption algorithm and key. On the other hand, a secure hash cannot be reversed. Once a message is hashed, it is transformed into a fixed-size output called a hash value, and it is computationally infeasible to retrieve the original message from the hash value. Therefore, the correct answer is "A cipher can be reversed, a hash cannot."
32.
A digital signature or digital signature scheme is a type of asymmetric cryptography. For messages sent through an insecure channel, a properly implemented digital signature gives the receiver reason to believe the message was sent by the claimed sender. While using a digital signature, the message digest is encrypted with which of the following keys?
Correct Answer
B. Senders private key
Explanation
A digital signature is created by encrypting the message digest with the sender's private key. This ensures the authenticity and integrity of the message, as only the sender possesses the private key required to encrypt the digest. The receiver can then verify the signature using the sender's public key, which allows them to confirm that the message was indeed sent by the claimed sender.
33.
Which key is generally applied FIRST to a message digest to provide non-repudiation by use of asymmetric cryptography?
Correct Answer
A. Private key of the sender
Explanation
The private key of the sender is generally applied first to a message digest to provide non-repudiation by use of asymmetric cryptography. This is because the private key is used for signing the message digest, which can only be decrypted by the corresponding public key held by the receiver. By using the private key of the sender, it ensures that the message can be verified as authentic and originated from the sender, providing non-repudiation.
34.
Which of the following would be an effective way to ensure that a compromised PKI key cannot access a system?
Correct Answer
D. Revoke the key
Explanation
Revoke the key would be an effective way to ensure that a compromised PKI key cannot access a system. When a key is revoked, it is invalidated and no longer trusted by the system. This prevents any unauthorized access or use of the compromised key, ensuring the security of the system.
35.
Which of the following would be an example of a hardware device where keys can be stored? (Select TWO)
Correct Answer(s)
C. Smart card
D. PCMCIA card
Explanation
A smart card is a hardware device that can store keys. It is a small plastic card that contains an embedded microchip. The microchip can store and process data, including encryption keys. Smart cards are commonly used for secure authentication and data storage purposes.
A PCMCIA card is another hardware device that can store keys. It is a credit card-sized device that can be inserted into a PCMCIA slot on a computer or other electronic device. PCMCIA cards can contain storage media, such as flash memory or hard drives, which can store encryption keys or other sensitive data.
36.
Pretty good privacy (PGP) uses a PKI Trust Model where no certificate authority (CA) is subordinate to another.The model with no single trusted root is known as:
Correct Answer
B. Peer-to-peer
Explanation
PGP uses a PKI Trust Model where no certificate authority (CA) is subordinate to another. This means that there is no single trusted root in the model. In a peer-to-peer trust model, each participant acts as both a client and a server, and they can independently verify the authenticity of each other's public keys. This decentralized approach allows for greater security and eliminates the need for a central authority. Therefore, the correct answer is peer-to-peer.
37.
Using software on an individual computer to generate a key pair is an example of which of the following approaches to PKI architecture?
Correct Answer
D. Decentralized
Explanation
Decentralized PKI architecture refers to a system where the generation and management of key pairs are distributed across individual computers. In this approach, each computer is responsible for generating its own key pair using software installed on the individual machine. This ensures that the control and ownership of the key pairs are distributed among multiple entities, reducing the risk of a single point of failure or compromise.
38.
How is it possible to be certain that when an employee leaves the company permanently, the company will have access to their private keys?
Correct Answer
B. Store the keys in escrow
Explanation
Storing the keys in escrow means that the company keeps a copy of the employee's private keys in a secure location. This ensures that even if the employee leaves the company permanently, the company will still have access to their private keys. By having access to the private keys, the company can continue to access any encrypted data or systems that were previously secured using those keys.
39.
CRL is short for Certificate Revocation List. Which types of keys are included in a CRL?
Correct Answer
B. Both public and private keys
Explanation
A Certificate Revocation List (CRL) is a list of digital certificates that have been revoked by the issuing Certificate Authority (CA) before their expiration date. It includes both public and private keys associated with these certificates. By including both types of keys, the CRL ensures that any entity relying on the certificates can verify their revocation status and prevent their use for secure communications.
40.
Which of the following are types of certificate-based authentication? (Select TWO)
Correct Answer(s)
B. One-to-one mapping
C. Many-to-one mapping
Explanation
Certificate-based authentication is a method of verifying the identity of a user or device using digital certificates. In this type of authentication, a certificate is issued by a trusted authority and is used to authenticate the identity of the user or device. One-to-one mapping refers to the use of a single certificate to authenticate a single user or device, while many-to-one mapping refers to the use of multiple certificates to authenticate a single user or device. Therefore, the correct answer is One-to-one mapping and Many-to-one mapping.
41.
PKI is a set of hardware, software, people, policies, and procedures needed to create, manage, store, distribute, and revoke digital certificates. The public key infrastructure is based on which encryption schemes?
Correct Answer
C. Asymmetric
Explanation
The correct answer is asymmetric. Public key infrastructure (PKI) is based on asymmetric encryption schemes. In asymmetric encryption, two different keys are used - a public key for encryption and a private key for decryption. This allows secure communication between parties without the need to share the private key. PKI utilizes this concept by using digital certificates that contain public keys, which can be used to verify the authenticity and integrity of digital communications.
42.
Which key can be used by a user to log into their network with a smart card?
Correct Answer
B. Private key
Explanation
A user can log into their network with a smart card using their private key. A smart card is a secure device that stores cryptographic keys and is used for authentication purposes. The private key is a unique key that is securely stored on the smart card and is used to decrypt information and authenticate the user's identity. By using the private key stored on the smart card, the user can securely access the network.
43.
Choose the scheme or system used by PGP (Pretty Good Privacy) to encrypt data:
Correct Answer
C. Asymmetric scheme
Explanation
PGP (Pretty Good Privacy) uses an asymmetric scheme to encrypt data. In this scheme, two different keys are used - a public key for encryption and a private key for decryption. The public key is shared with others, allowing them to encrypt data that can only be decrypted using the private key. This provides a secure way to transmit encrypted data without the need for a shared secret key.