CompTIA Security+ Question K-9

Which of the following is a security benefit of providing additional HVAC capacity or increased tonnage in a datacenter?

A. Increased availability of network services due to higher throughput
B. Longer MTBF of hardware due to lower operating temperatures
C. Higher data integrity due to more efficient SSD cooling
D. Longer UPS run time due to increased airflow

Answer: B

Explanation:
The mean time between failures (MTBF) is the measure of the anticipated incidence of failure for a system or component. This measurement determines the component’s anticipated lifetime. If the MTBF of a cooling system is one year, you can anticipate that the system will last for a one-year period; this means that you should be prepared to replace or rebuild the system once a year. If the system lasts longer than the MTBF, your organization receives a bonus. MTBF is helpful in evaluating a system’s reliability and life expectancy. Thus longer MTBF due to lower operating temperatures is a definite advantage

CompTIA Security+ Question K-3

A server administrator notes that a legacy application often stops running due to a memory error. When reviewing the debugging logs, they notice code being run calling an internal process to exploit the machine. Which of the following attacks does this describe?

A. Zero-day
B. Buffer overflow
C. Cross site scripting
D. Malicious add-on

Answer: B

Explanation:
This question describes a buffer overflow attack.

A buffer overflow occurs when a program or process tries to store more data in a buffer (temporary data storage area) than it was intended to hold. Since buffers are created to contain a finite amount of data, the extra information – which has to go somewhere – can overflow into adjacent buffers, corrupting or overwriting the valid data held in them. Although it may occur accidentally through programming error, buffer overflow is an increasingly common type of security attack on data integrity. In buffer overflow attacks, the extra data may contain codes designed to trigger specific actions, in effect sending new instructions to the attacked computer that could, for example, damage the user’s files, change data, or disclose confidential information. Buffer overflow attacks are said to have arisen because the C programming language supplied the framework, and poor programming practices supplied the vulnerability.

CompTIA Security+ Question I-82

A security administrator wants to test the reliability of an application which accepts user provided parameters. The administrator is concerned with data integrity and availability. Which of the following should be implemented to accomplish this task?

A. Secure coding
B. Fuzzing
C. Exception handling
D. Input validation

Answer: B

Explanation:
Fuzzing is a software testing technique that involves providing invalid, unexpected, or random data to as inputs to a computer program. The program is then monitored for exceptions such as crashes, or failed validation, or memory leaks.

CompTIA Security+ Question I-41

Which of the following is true about input validation in a client-server architecture, when data integrity is critical to the organization?

A. It should be enforced on the client side only.
B. It must be protected by SSL encryption.
C. It must rely on the user’s knowledge of the application.
D. It should be performed on the server side.

Answer: D

Explanation:
Client-side validation should only be used to improve user experience, never for security purposes. A client-side input validation check can improve application performance by catching malformed input on the client and, therefore, saving a roundtrip to the server. However, client side validation can be easily bypassed and should never be used for security purposes. Always use server-side validation to protect your application from malicious attacks.

CompTIA Security+ Question H-86

A security administrator wants to ensure that the message the administrator sends out to their Chief Financial Officer (CFO) does not get changed in route. Which of the following is the administrator MOST concerned with?

A. Data confidentiality
B. High availability
C. Data integrity
D. Business continuity

Answer: C

Explanation:
Integrity is the process of ensuring that the information has not been altered during transmission. This can be accomplished by means of hashing.

CompTIA Security+ Question H-43

To ensure compatibility with their flagship product, the security engineer is tasked to recommend an encryption cipher that will be compatible with the majority of third party software and hardware vendors. Which of the following should be recommended?

A. SHA
B. MD5
C. Blowfish
D. AES

Answer: D

Explanation:
AES (Advanced Encryption Standard) has been adopted by the U.S. government and is now used worldwide. It supersedes the Data Encryption Standard (DES) which was published in 1977. The algorithm described by AES is a symmetric-key algorithm, meaning the same key is used for both encrypting and decrypting the data. AES is used to encrypt data, not to verify data integrity.

CompTIA Security+ Question H-29

Failure to validate the size of a variable before writing it to memory could result in which of the following application attacks?

A. Malicious logic
B. Cross-site scripting
C. SQL injection
D. Buffer overflow

Answer: D

Explanation:
A buffer overflow occurs when a program or process tries to store more data in a buffer (temporary data storage area) than it was intended to hold. Since buffers are created to contain a finite amount of data, the extra information – which has to go somewhere – can overflow into adjacent buffers, corrupting or overwriting the valid data held in them. Although it may occur accidentally through programming error, buffer overflow is an increasingly common type of security attack on data integrity. In buffer overflow attacks, the extra data may contain codes designed to trigger specific actions, in effect sending new instructions to the attacked computer that could, for example, damage the user’s files, change data, or disclose confidential information. Validating the size of a variable before writing it to memory will ensure that the variable can fit into the buffer. Failure to validate the size of a variable before writing it to memory can result in a buffer overflow.

CompTIA Security+ Question H-17

Which of the following MUST Matt, a security administrator, implement to verify both the integrity and authenticity of a message while requiring a shared secret?

A. RIPEMD
B. MD5
C. SHA
D. HMAC

Answer: D

Explanation:
HMAC (Hash-Based Message Authentication Code) uses a hashing algorithm along with a symmetric key. The hashing function provides data integrity, while the symmetric key provides authenticity.

CompTIA Security+ Question G-93

A software company has completed a security assessment. The assessment states that the company should implement fencing and lighting around the property. Additionally, the assessment states that production releases of their software should be digitally signed. Given the recommendations, the company was deficient in which of the following core security areas? (Select TWO).

A. Fault tolerance
B. Encryption
C. Availability
D. Integrity
E. Safety
F. Confidentiality

Answer: D,E

Explanation:
Aspects such as fencing, proper lighting, locks, CCTV, Escape plans Drills, escape routes and testing controls form part of safety controls. Integrity refers to aspects such as hashing, digital signatures, certificates and non-repudiation – all of which has to do with data integrity.

CompTIA Security+ Question F-45

A network engineer is designing a secure tunneled VPN. Which of the following protocols would be the MOST secure?

A. IPsec
B. SFTP
C. BGP
D. PPTP

Answer: A

Explanation:
Layer 2 Tunneling Protocol (L2TP) came about through a partnership between Cisco and Microsoft with the intention of providing a more secure VPN protocol. L2TP is considered to be a more secure option than PPTP, as the IPSec protocol which holds more secure encryption algorithms, is utilized in conjunction with it. It also requires a pre-shared certificate or key. L2TP’s strongest level of encryption makes use of 168 bit keys, 3 DES encryption algorithm and requires two levels of authentication. L2TP has a number of advantages in comparison to PPTP in terms of providing data integrity and authentication of origin verification designed to keep hackers from compromising the system. However, the increased overhead required to manage this elevated security means that it performs at a slower pace than PPTP.