CompTIA Security+ Question L-40

The ore-sales engineering team needs to quickly provide accurate and up-to-date information to potential clients. This information includes design specifications and engineering data that is developed and stored using numerous applications across the enterprise. Which of the following authentication technique is MOST appropriate?

A. Common access cards
B. TOTP
C. Single sign-on
D. HOTP

Answer: B

CompTIA Security+ Question L-39

Which of the following types of authentication solutions use tickets to provide access to various resources from a central location?

A. Biometrics
B. PKI
C. ACLs
D. Kerberos

Answer: D

Explanation:
The basic process of Kerberos authentication is as follows: The subject provides logon credentials. The Kerberos client system encrypts the password and transmits the protected credentials to the KDC. The KDC verifies the credentials and then creates a ticket-granting ticket (TGT—a hashed form of the subject’s password with the addition of a time stamp that indicates a valid lifetime). The TGT is encrypted and sent to the client. The client receives the TGT. At this point, the subject is an authenticated principle in the Kerberos realm. The subject requests access to resources on a network server. This causes the client to request a service ticket (ST) from the KDC. The KDC verifies that the client has a valid TGT and then issues an ST to the client. The ST includes a time stamp that indicates its valid lifetime. The client receives the ST. The client sends the ST to the network server that hosts the desired resource. The network server verifies the ST. If it’s verified, it initiates a communication session with the client. From this point forward, Kerberos is no longer involved.

CompTIA Security+ Question L-38

Encryption used by RADIUS is BEST described as:

A. Quantum
B. Elliptical curve
C. Asymmetric
D. Symmetric

Answer: D

Explanation:
The RADIUS server uses a symmetric encryption method. Note: Symmetric algorithms require both ends of an encrypted message to have the same key and processing algorithms. Symmetric algorithms generate a secret key that must be protected.

CompTIA Security+ Question L-37

After a recent internal audit, the security administrator was tasked to ensure that all credentials must be changed within 90 days, cannot be repeated, and cannot contain any dictionary words or patterns. All credentials will remain enabled regardless of the number of attempts made. Which of the following types of user account options were enforced? (Select TWO).

A. Recovery
B. User assigned privileges
C. Lockout
D. Disablement
E. Group based privileges
F. Password expiration
G. Password complexity

Answer: F,G

Explanation:
Password complexity often requires the use of a minimum of three out of four standard character types for a password. The more characters in a password that includes some character type complexity, the more resistant it is to password-cracking techniques. In most cases, passwords are set to expire every 90 days.

CompTIA Security+ Question L-36

Which of the following types of attacks involves interception of authentication traffic in an attempt to gain unauthorized access to a wireless network?

A. Near field communication
B. IV attack
C. Evil twin
D. Replay attack

Answer: B

Explanation:
An initialization vector is a random number used in combination with a secret key as a means to encrypt data. This number is sometimes referred to as a nonce, or “number occurring once,” as an encryption program uses it only once per session. An initialization vector is used to avoid repetition during the data encryption process, making it impossible for hackers who use dictionary attack to decrypt the exchanged encrypted message by discovering a pattern. This is known as an IV attack. A particular binary sequence may be repeated more than once in a message, and the more it appears, the more the encryption method is discoverable. For example if a one-letter word exists in a message, it may be either “a” or “I” but it can’t be “e” because the word “e” is non-sensical in English, while “a” has a meaning and “I” has a meaning. Repeating the words and letters makes it possible for software to apply a dictionary and discover the binary sequence corresponding to each letter. Using an initialization vector changes the binary sequence corresponding to each letter, enabling the letter “a” to be represented by a particular sequence in the first instance, and then represented by a completely different binary sequence in the second instance.

WEP (Wireless Equivalent Privacy) is vulnerable to an IV attack. Because RC4 is a stream cipher, the same traffic key must never be used twice. The purpose of an IV, which is transmitted as plain text, is to prevent any repetition, but a 24-bit IV is not long enough to ensure this on a busy network. The way the IV was used also opened WEP to a related key attack. For a 24-bit IV, there is a 50% probability the same IV will repeat after 5000 packets.

CompTIA Security+ Question L-35

The Chief Information Officer (CIO) receives an anonymous threatening message that says “beware of the 1st of the year”. The CIO suspects the message may be from a former disgruntled employee planning an attack.
Which of the following should the CIO be concerned with?

A. Smurf Attack
B. Trojan
C. Logic bomb
D. Virus

Answer: C

Explanation:
A logic bomb is a piece of code intentionally inserted into a software system that will set off a malicious function when specified conditions are met. For example, a programmer may hide a piece of code that starts deleting files should they ever be terminated from the company. Software that is inherently malicious, such as viruses and worms, often contain logic bombs that execute a certain payload at a pre-defined time or when some other condition is met. This technique can be used by a virus or worm to gain momentum and spread before being noticed. Some viruses attack their host systems on specific dates, such as Friday the 13th or April Fool’s Day. Trojans that activate on certain dates are often called “time bombs”. To be considered a logic bomb, the payload should be unwanted and unknown to the user of the software. As an example, trial programs with code that disables certain functionality after a set time are not normally regarded as logic bombs.

CompTIA Security+ Question L-34

Which of the following is the MOST intrusive type of testing against a production system?

A. White box testing
B. War dialing
C. Vulnerability testing
D. Penetration testing

Answer: D

Explanation:
Penetration testing is the most intrusive type of testing because you are actively trying to circumvent the system’s security controls to gain access to the system. Penetration testing (also called pen testing) is the practice of testing a computer system, network or Web application to find vulnerabilities that an attacker could exploit. Pen tests can be automated with software applications or they can be performed manually. Either way, the process includes gathering information about the target before the test (reconnaissance), identifying possible entry points, attempting to break in (either virtually or for real) and reporting back the findings. The main objective of penetration testing is to determine security weaknesses. A pen test can also be used to test an organization’s security policy compliance, its employees’ security awareness and the organization’s ability to identify and respond to security incidents. Penetration tests are sometimes called white hat attacks because in a pen test, the good guys are attempting to break in.

Pen test strategies include:

Targeted testing Targeted testing is performed by the organization’s IT team and the penetration testing team working together. It’s sometimes referred to as a “lights-turned-on” approach because everyone can see the test being carried out.

External testing This type of pen test targets a company’s externally visible servers or devices including domain name servers (DNS), e-mail servers, Web servers or firewalls. The objective is to find out if an outside attacker can get in and how far they can get in once they’ve gained access.

Internal testing This test mimics an inside attack behind the firewall by an authorized user with standard access privileges. This kind of test is useful for estimating how much damage a disgruntled employee could cause.

Blind testing A blind test strategy simulates the actions and procedures of a real attacker by severely limiting the information given to the person or team that’s performing the test beforehand. Typically, they may only be given the name of the company. Because this type of test can require a considerable amount of time for reconnaissance, it can be expensive.

Double blind testing Double blind testing takes the blind test and carries it a step further. In this type of pen test, only one or two people within the organization might be aware a test is being conducted. Double-blind tests can be useful for testing an organization’s security monitoring and incident identification as well as its response procedures.

CompTIA Security+ Question L-33

The database server used by the payroll system crashed at 3 PM and payroll is due at 5 PM. Which of the following metrics is MOST important is this instance?

A. ARO
B. SLE
C. MTTR
D. MTBF

Answer: C

CompTIA Security+ Question L-32

A security administrator discovers an image file that has several plain text documents hidden in the file. Which of the following security goals is met by camouflaging data inside of other files?

A. Integrity
B. Confidentiality
C. Steganography
D. Availability

Answer: C

Explanation:
Steganography is the process of concealing a file, message, image, or video within another file, message, image, or video. Note: The advantage of steganography over cryptography alone is that the intended secret message does not attract attention to itself as an object of scrutiny. Plainly visible encrypted messages, no matter how unbreakable will arouse interest, and may in themselves be incriminating in countries where encryption is illegal. Thus, whereas cryptography is the practice of protecting the contents of a message alone, steganography is concerned with concealing the fact that a secret message is being sent, as well as concealing the contents of the message.

CompTIA Security+ Question L-31

An organization is implementing a password management application which requires that all local administrator passwords be stored and automatically managed. Auditors will be responsible for monitoring activities in the application by reviewing the logs. Which of the following security controls is the BEST option to prevent auditors from accessing or modifying passwords in the application?

A. Time of day restrictions
B. Create user accounts for the auditors and assign read-only access
C. Mandatory access control
D. Role-based access with read-only

Answer: D

Explanation:
Auditors (employees performing the auditor role) will have access application by reviewing the logs. We can therefore assign access based on employee role. This is an example of Role-based access control (RBAC). To prevent the auditors from modifying passwords in the application, we need to ensure that they do not have write access. Therefore, you should assign only read access.

Role-Based Access Control (RBAC) models approach the problem of access control based on established roles in an organization. RBAC models implement access by job function or by responsibility. Each employee has one or more roles that allow access to specific information. If a person moves from one role to another, the access for the previous role will no longer be available. Instead of thinking “Denise needs to be able to edit files,” RBAC uses the logic “Editors need to be able to edit files” and “Denise is a member of the Editors group.” This model is always good for use in an environment in which there is high employee turnover.