CompTIA Security+ Question L-16

A company’s employees were victims of a spear phishing campaign impersonating the CEO. The company would now like to implement a solution to improve the overall security posture by assuring their employees that email originated from the CEO. Which of the following controls could they implement to BEST meet this goal?

A. Spam filter
B. Digital signatures
C. Antivirus software
D. Digital certificates

Answer: B

A digital signature is a mathematical technique used to validate the authenticity and integrity of a message, software, or digital document. The digital equivalent of a handwritten signature or stamped seal, but offering far more inherent security, a digital signature is intended to solve the problem of tampering and impersonation in digital communications. Digital signatures can provide the added assurances of evidence to origin, identity and status of an electronic document, transaction or message, as well as acknowledging informed consent by the signer. Digital signatures are based on public key cryptography, also known as asymmetric cryptography. Using a public key algorithm such as RSA, one can generate two keys that are mathematically linked: one private and one public. To create a digital signature, signing software (such as an email program) creates a one-way hash of the electronic data to be signed. The private key is then used to encrypt the hash. The encrypted hash — along with other information, such as the hashing algorithm — is the digital signature. The reason for encrypting the hash instead of the entire message or document is that a hash function can convert an arbitrary input into a fixed length value, which is usually much shorter. This saves time since hashing is much faster than signing.

CompTIA Security+ Question G-32

Which of the following is the BEST approach to perform risk mitigation of user access control rights?

A. Conduct surveys and rank the results.
B. Perform routine user permission reviews.
C. Implement periodic vulnerability scanning.
D. Disable user accounts that have not been used within the last two weeks.

Answer: B

Risk mitigation is accomplished any time you take steps to reduce risk. This category includes installing antivirus software, educating users about possible threats, monitoring network traffic, adding a firewall, and so on. User permissions may be the most basic aspect of security and is best coupled with a principle of least privilege. And related to permissions is the concept of the access control list (ACL). An ACL is literally a list of who can access what resource and at what level. Thus the best risk mitigation steps insofar as access control rights are concerned, is the regular/routine review of user permissions.

CompTIA Security+ Question G-5

The librarian wants to secure the public Internet kiosk PCs at the back of the library. Which of the following would be the MOST appropriate? (Select TWO).

A. Device encryption
B. Antivirus
C. Privacy screen
D. Cable locks
E. Remote wipe

Answer: B,D

B: Antivirus software is used to protect systems against viruses, which are a form of malicious code designed to spread from one system to another, consuming network resources. Public systems are particularly prone to viruses.

D: Cable locks are theft deterrent devices that can be used to tether a device to a fixed point keep devices from being easy to steal.

CompTIA Security+ Question F-15

After working on his doctoral dissertation for two years, Peter, a user, is unable to open his dissertation file. The screen shows a warning that the dissertation file is corrupted because it is infected with a backdoor, and can only be recovered by upgrading the antivirus software from the free version to the commercial version. Which of the following types of malware is the laptop MOST likely infected with?

A. Ransomware
B. Trojan
C. Backdoor
D. Armored virus

Answer: A

Ransomware is a type of malware which restricts access to the computer system that it infects, and demands a ransom paid to the creator(s) of the malware in order for the restriction to be removed. Some forms of ransomware encrypt files on the system’s hard drive), while some may simply lock the system and display messages intended to coax the user into paying. Ransomware typically propagates as a trojan like a conventional computer worm, entering a system through, for example, a downloaded file or a vulnerability in a network service. The program will then run a payload: such as one that will begin to encrypt personal files on the hard drive. More sophisticated ransomware may hybrid-encrypt the victim’s plaintext with a random symmetric key and a fixed public key. The malware author is the only party that knows the needed private decryption key. Some ransomware payloads do not use encryption. In these cases, the payload is simply an application designed to restrict interaction with the system, typically by setting the Windows Shell to itself, or even modifying the master boot record and/or partition table (which prevents the operating system from booting at all until it is repaired) Ransomware payloads utilize elements of scareware to extort money from the system’s user. The payload may, for example, display notices purportedly issued by companies or law enforcement agencies which falsely claim that the system had been used for illegal activities, or contains illegal content such as pornography and pirated software or media. Some ransomware payloads imitate Windows’ product activation notices, falsely claiming that their computer’s Windows installation is counterfeit or requires re-activation. These tactics coax the user into paying the malware’s author to remove the ransomware, either by supplying a program which can decrypt the files, or by sending an unlock code that undoes the changes the payload has made.

CompTIA Security+ Question E-11

Which of the following is described as an attack against an application using a malicious file?

A. Client side attack
B. Spam
C. Impersonation attack
D. Phishing attack

Answer: A

In this question, a malicious file is used to attack an application. If the application is running on a client computer, this would be a client side attack. Attacking a service or application on a server would be a server side attack.

Client-side attacks target vulnerabilities in client applications interacting with a malicious data. The difference is the client is the one initiating the bad connection. Client-side attacks are becoming more popular. This is because server side attacks are not as

easy as they once were according to Attackers are finding success going after weaknesses in desktop applications such as browsers, media players, common office applications and e-mail clients. To defend against client-side attacks keep-up the most current application patch levels, keep antivirus software updated and keep authorized software to a minimum.

CompTIA Security+ Question D-62

Concurrent use of a firewall, content filtering, antivirus software and an IDS system would be considered components of:

A. Redundant systems.
B. Separation of duties.
C. Layered security.
D. Application control.

Answer: C

Layered security is the practice of combining multiple mitigating security controls to protect resources and data.

CompTIA Security+ Question A-80

A network administrator identifies sensitive files being transferred from a workstation in the LAN to an unauthorized outside IP address in a foreign country. An investigation determines that the firewall has not been altered, and antivirus is up-to-date on the workstation. Which of the following is the MOST likely reason for the incident?

A. MAC Spoofing
B. Session Hijacking
C. Impersonation
D. Zero-day

Answer: D

This question states that antivirus is up-to-date on the workstation and the firewall has not been altered. The antivirus software is up to date with all ‘known’ viruses. A zero day vulnerability is an unknown vulnerability so a patch or virus definition has not been released yet.

A zero day vulnerability refers to a hole in software that is unknown to the vendor. This security hole is then exploited by hackers before the vendor becomes aware and hurries to fix it—this exploit is called a zero day attack. Uses of zero day attacks can include infiltrating malware, spyware or allowing unwanted access to user information. The term “zero day” refers to the unknown nature of the hole to those outside of the hackers, specifically, the developers. Once the vulnerability becomes known, a race begins for the developer, who must protect users.

CompTIA Security+ Question A-11

A company is looking to improve their security posture by addressing risks uncovered by a recent penetration test. Which of the following risks is MOST likely to affect the business on a day-to-day basis?

A. Insufficient encryption methods
B. Large scale natural disasters
C. Corporate espionage
D. Lack of antivirus software

Answer: D

The most common threat to computers is computer viruses. A computer can become infected with a virus through day-to-day activities such as browsing web sites or emails. As browsing and opening emails are the most common activities performed by all users, computer viruses represent the most likely risk to a business.

CompTIA Security+ Simulation 7

A Security administrator wants to implement strong security on the company smart phones and terminal servers located in the data center. Drag and Drop the applicable controls to each asset type.

Instructions: Controls can be used multiple times and not all placeholders needs to be filled. When you have completed the simulation, Please select Done to submit.

Correct Answer:

Cable locks are used as a hardware lock mechanism – thus best used on a Data Center Terminal Server.

Network monitors are also known as sniffers – thus best used on a Data Center Terminal Server.

Install antivirus software. Antivirus software should be installed and definitions kept current on all hosts. Antivirus software should run on the server as well as on every workstation. In addition to active monitoring of incoming fi les, scans should be conducted regularly to catch any infections that have slipped through- thus best used on a Data Center Terminal Server.

Proximity readers are used as part of physical barriers which makes it more appropriate to use on a center’s entrance to protect the terminal server.

Mentor app is an Apple application used for personal development and is best used on a mobile device such as a smart phone.

Remote wipe is an application that can be used on devices that are stolen to keep data safe. It is basically a command to a phone that will remotely clear the data on that phone. This process is known as a remote wipe, and it is intended to be used if the phone is stolen or going to another user.

Should a device be stolen, GPS (Global Positioning System) tracking can be used to identify its location and allow authorities to find it – thus best used on a smart phone.

Screen Lock is where the display should be configured to time out after a short period of inactivity and the screen locked with a password. To be able to access the system again, the user must provide the password. After a certain number of attempts, the user should not be allowed to attempt any additional logons; this is called lockout – thus best used on a smart phone.

Strong Password since passwords are always important, but even more so when you consider that the device could be stolen and in the possession of someone who has unlimited access and time to try various values – thus best use strong passwords on a smartphone as it can be stolen more easily than a terminal server in a data center.

Device Encryption- Data should be encrypted on the device so that if it does fall into the wrong hands, it cannot be accessed in a usable form without the correct passwords. It is recommended to you use Trusted Platform Module (TPM) for all mobile devices where possible.

Use pop-up blockers. Not only are pop-ups irritating, but they are also a security threat. Pop-ups (including pop-unders) represent unwanted programs running on the system, and they can jeopardize the system’s well-being. This will be more effective on a mobile device rather than a terminal server.

Use host-based firewalls. A firewall is the first line of defense against attackers and malware. Almost every current operating system includes a firewall, and most are turned on by Default- thus best used on a Data Center Terminal Server.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex,

CompTIA Network+ Question A-91

Users have reported poor network performance. A technician suspects a user may have maliciously flooded the network with ping request. Which of the following should the technician implement to avoid potential occurrences from happening in the future?

A. Block all ICMP request
B. Update all antivirus software
C. Remove all suspected users from the network
D. Upgrade firmware on all network cards

Correct Answer: A