CAS-003 CompTIA Exam Questions and Free Practice Test

Question 19

An engineer is assisting with the design of a new virtualized environment that will house critical company services and reduce the datacenter’s physical footprint. The company has expressed concern about the integrity of operating systems and wants to ensure a vulnerability explogted in one datacenter segment would not lead to the compromise of all others. Which of the following design objectives should the engineer complete to BEST mitigate the company’s concerns? (Choose two.)

A. Deploy virtual desktop infrastructure with an OOB management network

B. Employ the use of vTPM with boot attestation

C. Leverage separate physical hardware for sensitive services and data

D. Use a community CSP with independently managed security services

E. Deploy to a private cloud with hosted hypervisors on each physical machine

Correct Answer:AC

Question 20

A systems administrator at a medical imaging company discovers protected health information (PHI) on a general purpose file server. Which of the following steps should the administrator take NEXT?

A. Isolate all of the PHI on its own VLAN and keep it segregated at Layer 2

B. Immediately encrypt all PHI with AES 256

C. Delete all PHI from the network until the legal department is consulted

D. Consult the legal department to determine legal requirements

Correct Answer:B

Question 21

An administrator has enabled salting for users' passwords on a UNIX box. A penetration tester must attempt to retrieve password hashes. Which of the following files must the penetration tester use to eventually obtain passwords on the system? (Select TWO).

A. /etc/passwd

B. /etc/shadow

C. /etc/security

D. /etc/password

E. /sbin/logon

F. /bin/bash

Correct Answer:AB
In cryptography, a salt is random data that is used as an additional input to a one-way function that hashes a password or passphrase. In this question, enabling salting for users' passwords means to store the passwords in an encrypted format.
Traditional Unix systems keep user account information, including one-way encrypted passwords, in a text file called ``/etc/passwd''. As this file is used by many tools (such as ``ls'') to display file ownerships, etc. by matching user id #'s with the user's names, the file needs to be world-readable. Consequentially, this can be somewhat of a security risk.
Another method of storing account information is with the shadow password format. As with the traditional method, this method stores account information in the /etc/passwd file in a compatible
format. However, the password is stored as a single "x" character (ie. not actually stored in this file). A second file, called ``/etc/shadow'', contains encrypted password as well as other information such as account or password expiration values, etc.
Incorrect Answers:
C: The /etc/security file contains group information. It does not contain usernames or passwords. D: There is no /etc/password file. Usernames are stored in the /etc/passwd file.
E: There is no /sbin/logon file. Usernames are stored in the /etc/passwd file.
F: /bin/bash is a UNIX shell used to run a script. It is not where usernames or passwords are stored. References:
http://www.tldp.org/LDP/lame/LAME/linux-admin-made-easy/shadow-file-formats.HYPERLINK "http://www.tldp.org/LDP/lame/LAME/linux-admin-made-easy/shadow-file-formats.html"html

Question 22

A developer is determining the best way to improve security within the code being developed. The developer is focusing on input fields where customers enter their credit card details. Which of the following techniques, if implemented in the code, would be the MOST effective in protecting the fields from malformed input?

A. Client side input validation

B. Stored procedure

C. Encrypting credit card details

D. Regular expression matching

Correct Answer:D
Regular expression matching is a technique for reading and validating input, particularly in web software. This question is asking about securing input fields where customers enter their credit card details. In this case, the expected input into the credit card number field would be a sequence of numbers of a certain length. We can use regular expression matching to verify that the input is indeed a sequence of numbers. Anything that is not a sequence of numbers could be malicious code. Incorrect Answers:
A: Client side input validation could be used to validate the input into input fields. Client side input validation is where the validation is performed by the web browser. However this question is asking for the BEST answer. A user with malicious intent could bypass the client side input validation whereas it would be much more difficult to bypass regular expression matching implemented in the application code.
B: A stored procedure is SQL code saved as a script. A SQL user can run the stored procedure rather than typing all the SQL code contained in the stored procedure. A stored procedure is not used for
validating input.
C: Any stored credit card details should be encrypted for security purposes. Also a secure method of transmission such as SSL or TLS should be used to encrypt the data when transmitting the credit card number over a network such as the Internet. However, encrypting credit card details is not a way of securing the input fields in an application.

Question 23

A new internal network segmentation solution will be implemented into the enterprise that consists of 200 internal firewalls. As part of running a pilot exercise, it was determined that it takes three changes to deploy a new application onto the network before it is operational. Security now has a
significant effect on overall availability. Which of the following would be the FIRST process to perform
as a result of these findings?

A. Lower the SLA to a more tolerable level and perform a risk assessment to see if the solution could be met by another solutio

B. Reuse the firewall infrastructure on other projects.

C. Perform a cost benefit analysis and implement the solution as it stands as long as the risks are understood by the business owners around the availability issue

D. Decrease the current SLA expectations to match the new solution.

E. Engage internal auditors to perform a review of the project to determine why and how the project did not meet the security requirement

F. As part of the review ask them to review the control effectiveness.

G. Review to determine if control effectiveness is in line with the complexity of the solutio

H. Determine if the requirements can be met with a simpler solution.

Correct Answer:D
Checking whether control effectiveness complies with the complexity of the solution and then determining if there is not an alternative simpler solution would be the first procedure to follow in the light of the findings.
Incorrect Answers:
A: The SLA is in essence a contracted level of guaranteed service between thee cloud provider and the customer, of a certain level of protection, SLA’s also define targets for hardware and software, thus lowering the SLA is not an option.
B: A cost benefit analysis focus on calculating the costs, the benefits and then compare the results in order to see if the proposed solution is viable and whether the benefits outweigh the risks/costs. However, it is not good practice to lower the SLA.
C: Performing reviews are only done after implementation. References:
Gregg, Michael, and Billy Haines, CASP CompTIA Advanced Security Practitioner Study Guide, John Wiley & Sons, Indianapolis, 2012, pp. 199, 297-299

Question 24

Following a security assessment, the Chief Information Security Officer (CISO) is reviewing the results of the assessment and evaluating potential risk treatment strategies. As part of the CISO’s
evaluation, a judgment of potential impact based on the identified risk is performed. To prioritize response actions, the CISO uses past experience to take into account the exposure factor as well as the external accessibility of the weakness identified. Which of the following is the CISO performing?

A. Documentation of lessons learned

B. Quantitative risk assessment

C. Qualitative assessment of risk

D. Business impact scoring

E. Threat modeling

Correct Answer:B

START CAS-003 EXAM