CompTIA Security+ Question K-35

Due to limited resources, a company must reduce their hardware budget while still maintaining availability. Which of the following would MOST likely help them achieve their objectives?

A. Virtualization
B. Remote access
C. Network access control
D. Blade servers

Answer: A

Explanation:
Because Virtualization allows a single set of hardware to host multiple virtual machines, it requires less hardware to maintain the current scenario.

CompTIA Security+ Question J-39

On Monday, all company employees report being unable to connect to the corporate wireless network, which uses 802.1x with PEAP. A technician verifies that no configuration changes were made to the wireless network and its supporting infrastructure, and that there are no outages.
Which of the following is the MOST likely cause for this issue?

A. Too many incorrect authentication attempts have caused users to be temporarily disabled.
B. The DNS server is overwhelmed with connections and is unable to respond to queries.
C. The company IDS detected a wireless attack and disabled the wireless network.
D. The Remote Authentication Dial-In User Service server certificate has expired.

Answer: D

Explanation:
The question states that the network uses 802.1x with PEAP. The 802.1x authentication server is typically an EAP-compliant Remote Access Dial-In User Service (RADIUS). A RADIUS server will be configured with a digital certificate. When a digital certificate is created, an expiration period is configured by the Certificate Authority (CA). The expiration period is commonly one or two years. The question states that no configuration changes have been made so it’s likely that the certificate has expired.

CompTIA Security+ Question I-96

Two programmers write a new secure application for the human resources department to store personal identifiable information. The programmers make the application available to themselves using an uncommon port along with an ID and password only they know. This is an example of which of the following?

A. Root Kit
B. Spyware
C. Logic Bomb
D. Backdoor

Answer: D

Explanation:
A backdoor in a computer system (or cryptosystem or algorithm) is a method of bypassing normal authentication, securing unauthorized remote access to a computer, obtaining access to plaintext, and so on, while attempting to remain undetected. The backdoor may take the form of an installed program (e.g., Back Orifice) or may subvert the system through a rootkit. A backdoor in a login system might take the form of a hard coded user and password combination which gives access to the system. Although the number of backdoors in systems using proprietary software (software whose source code is not publicly available) is not widely credited, they are nevertheless frequently exposed. Programmers have even succeeded in secretly installing large amounts of benign code as Easter eggs in programs, although such cases may involve official forbearance, if not actual permission. Many computer worms, such as Sobig and Mydoom, install a backdoor on the affected computer (generally a PC on broadband running Microsoft Windows and Microsoft Outlook). Such backdoors appear to be installed so that spammers can send junk e-mail from the infected machines. Others, such as the Sony/BMG rootkit distributed silently on millions of music CDs through late 2005, are intended as DRM measures—and, in that case, as data gathering agents, since both surreptitious programs they installed routinely contacted central servers.

CompTIA Security+ Question G-97

The security administrator notices a user logging into a corporate Unix server remotely as root. Which of the following actions should the administrator take?

A. Create a firewall rule to block SSH
B. Delete the root account
C. Disable remote root logins
D. Ensure the root account has a strong password

Answer: C

Explanation:
Remote users log in to Unix or Linux servers by using SSH. Although SSH is secure, allowing remote access as root is a security risk.

One of the biggest security holes you could open on a Unix or Linux server is to allow directly logging in as root through SSH, because any cracker can attempt to brute force your root password and potentially get access to your system if they can figure out your password. It’s much better to have a separate account that you regularly use and simply sudo to root when necessary. You should disable root ssh access by editing /etc/ssh/sshd_config to contain: PermitRootLogin no

CompTIA Security+ Question G-80

Ann, a software developer, has installed some code to reactivate her account one week after her account has been disabled. Which of the following is this an example of? (Select TWO).

A. Rootkit
B. Logic Bomb
C. Botnet
D. Backdoor
E. Spyware

Answer: B,D

Explanation:
This is an example of both a logic bomb and a backdoor. The logic bomb is configured to ‘go off’ or activate one week after her account has been disabled. The reactivated account will provide a backdoor into the system. 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. A backdoor in a computer system (or cryptosystem or algorithm) is a method of bypassing normal authentication, securing unauthorized remote access to a computer, obtaining access to plaintext, and so on, while attempting to remain undetected. The backdoor may take the form of an installed program (e.g., Back Orifice) or may subvert the system through a rootkit. A backdoor in a login system might take the form of a hard coded user and password combination which gives access to the system.

CompTIA Security+ Question G-73

Which of the following is mainly used for remote access into the network?

A. XTACACS
B. TACACS+
C. Kerberos
D. RADIUS

Answer: D

Explanation:
Most gateways that control access to the network have a RADIUS client component that communicates with the RADIUS server. Therefore, it can be inferred that RADIUS is primarily used for remote access.

CompTIA Security+ Question C-61

The Chief Technology Officer (CTO) wants to improve security surrounding storage of customer passwords.
The company currently stores passwords as SHA hashes. Which of the following can the CTO implement requiring the LEAST change to existing systems?

A. Smart cards
B. TOTP
C. Key stretching
D. Asymmetric keys

Answer: A

Explanation:
Smart cards usually come in two forms. The most common takes the form of a rectangular piece of plastic with an embedded microchip. The second is as a USB token. It contains a built in processor and has the ability to securely store and process information. A “contact” smart card communicates with a PC using a smart card reader whereas a “contactless” card sends encrypted information via radio waves to the PC. Typical scenarios in which smart cards are used include interactive logon, e-mail signing, e-mail decryption and remote access authentication. However, smart cards are programmable and can contain programs and data for many different applications. For example smart cards may be used to store medical histories for use in emergencies, to make electronic cash payments or to verify the identity of a customer to an e-retailer. Microsoft provides two device independent APIs to insulate application developers from differences between current and future implementations: CryptoAPI and Microsoft Win32® SCard APIs. The Cryptography API contains functions that allow applications to encrypt or digitally sign data in a flexible manner, while providing protection for the user’s sensitive private key data. All cryptographic operations are performed by independent modules known as cryptographic service providers (CSPs). There are many different cryptographic algorithms and even when implementing the same algorithm there are many choices to make about key sizes and padding for example. For this reason, CSPs are grouped into types, in which each supported CryptoAPI function, by default, performs in a way particular to that type. For example, CSPs in the PROV_DSS provider type support DSS Signatures and MD5 and SHA hashing.

CompTIA Security+ Question C-43

Ann has recently transferred from the payroll department to engineering. While browsing file shares, Ann notices she can access the payroll status and pay rates of her new coworkers. Which of the following could prevent this scenario from occurring?

A. Credential management
B. Continuous monitoring
C. Separation of duties
D. User access reviews

Answer: D

Explanation:
In addition to assigning user access properly, it is important to review that access periodically. Access review is a process to determine whether a user’s access level is still appropriate. People’s roles within an organization can change over time. It is important to review user accounts periodically and determine if they still require the access they currently have. An example of such a scenario would be a network administrator who was responsible for the domain controller but then moved over to administer the remote access servers. The administrator’s access to the domain controller should now be terminated. This concept of access review is closely related to the concept of least privileges. It is important that users do not have “leftover” privileges from previous job roles.

CompTIA Security+ Question C-10

Which of the following would Peter, a security administrator, MOST likely implement in order to allow employees to have secure remote access to certain internal network services such as file servers?

A. Packet filtering firewall
B. VPN gateway
C. Switch
D. Router

Answer: B

Explanation:
VPNs are usually employed to allow remote access users to connect to and access the network, and offer connectivity between two or more private networks or LANs. A VPN gateway (VPN router) is a connection point that connects two LANs via a nonsecure network such as the Internet.

CompTIA Security+ Question B-77

A trojan was recently discovered on a server. There are now concerns that there has been a security breach that allows unauthorized people to access data. The administrator should be looking for the presence of a/an:

A. Logic bomb.
B. Backdoor.
C. Adware application.
D. Rootkit.

Answer: B

Explanation:
There has been a security breach on a computer system. The security administrator should now check for the existence of a backdoor. A backdoor in a computer system (or cryptosystem or algorithm) is a method of bypassing normal authentication, securing unauthorized remote access to a computer, obtaining access to plaintext, and so on, while attempting to remain undetected. The backdoor may take the form of an installed program (e.g., Back Orifice) or may subvert the system through a rootkit. A backdoor in a login system might take the form of a hard coded user and password combination which gives access to the system. Although the number of backdoors in systems using proprietary software (software whose source code is not publicly available) is not widely credited, they are nevertheless frequently exposed. Programmers have even succeeded in secretly installing large amounts of benign code as Easter eggs in programs, although such cases may involve official forbearance, if not actual permission. Many computer worms, such as Sobig and Mydoom, install a backdoor on the affected computer (generally a PC on broadband running Microsoft Windows and Microsoft Outlook). Such backdoors appear to be installed so that spammers can send junk e-mail from the infected machines. Others, such as the Sony/BMG rootkit distributed silently on millions of music CDs through late 2005, are intended as DRM measures—and, in that case, as data gathering agents, since both surreptitious programs they installed routinely contacted central servers.