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 J-51

Which of the following describes a type of malware which is difficult to reverse engineer in a virtual lab?

A. Armored virus
B. Polymorphic malware
C. Logic bomb
D. Rootkit

Answer: A

Explanation:
An armored virus is a type of virus that has been designed to thwart attempts by analysts from examining its code by using various methods to make tracing, disassembling and reverse engineering more difficult. An Armored Virus may also protect itself from antivirus programs, making it more difficult to trace. To do this, the Armored Virus attempts to trick the antivirus program into believing its location is somewhere other than where it really is on the system.

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 I-7

Which of the following is an attack designed to activate based on time?

A. Logic Bomb
B. Backdoor
C. Trojan
D. Rootkit

Answer: A

CompTIA Security+ Question H-62

During a server audit, a security administrator does not notice abnormal activity. However, a network security analyst notices connections to unauthorized ports from outside the corporate network. Using specialized tools, the network security analyst also notices hidden processes running. Which of the following has MOST likely been installed on the server?

A. SPIM
B. Backdoor
C. Logic bomb
D. Rootkit

Answer: D

Explanation:
A rootkit is a collection of tools (programs) that enable administrator-level access to a computer or computer network. Typically, a cracker installs a rootkit on a computer after first obtaining user-level access, either by exploiting a known vulnerability or cracking a password. Once the rootkit is installed, it allows the attacker to mask intrusion and gain root or privileged access to the computer and, possibly, other machines on the network. A rootkit may consist of spyware and other programs that: monitor traffic and keystrokes; create a “backdoor” into the system for the hacker’s use; alter log files; attack other machines on the network; and alter existing system tools to escape detection. The presence of a rootkit on a network was first documented in the early 1990s. At that time, Sun and Linux operating systems were the primary targets for a hacker looking to install a rootkit. Today, rootkits are available for a number of operating systems, including Windows, and are increasingly difficult to detect on any network.

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-78

Which of the following malware types is MOST likely to execute its payload after Jane, an employee, has left the company?

A. Rootkit
B. Logic bomb
C. Worm
D. Botnet

Answer: B

Explanation:
This is an example of a logic bomb. The logic bomb is configured to ‘go off’ or when Jane has left the company. 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 F-33

One month after a software developer was terminated the helpdesk started receiving calls that several employees’ computers were being infected with malware. Upon further research, it was determined that these employees had downloaded a shopping toolbar. It was this toolbar that downloaded and installed the errant code. Which of the following attacks has taken place?

A. Logic bomb
B. Cross-site scripting
C. SQL injection
D. Malicious add-on

Answer: A

CompTIA Security+ Question E-88

A user casually browsing the Internet is redirected to a warez site where a number of pop-ups appear. After clicking on a pop-up to complete a survey, a drive-by download occurs. Which of the following is MOST likely to be contained in the download?

A. Backdoor
B. Spyware
C. Logic bomb
D. DDoS
E. Smurf

Answer: B

Explanation:
Explanation Spyware is software that is used to gather information about a person or organization without their knowledge and sends that information to another entity. Whenever spyware is used for malicious purposes, its presence is typically hidden from the user and can be difficult to detect. Some spyware, such as keyloggers, may be installed by the owner of a shared, corporate, or public computer intentionally in order to monitor users.

CompTIA Security+ Question E-19

Several users’ computers are no longer responding normally and sending out spam email to the users’ entire contact list. This is an example of which of the following?

A. Trojan virus
B. Botnet
C. Worm outbreak
D. Logic bomb

Answer: C

Explanation:
A worm is similar to a virus but is typically less malicious. A virus will usually cause damage to the system or files whereas a worm will usually just spread itself either using the network or by sending emails. A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. Often, it uses a computer network to spread itself, relying on security failures on the target computer to access it. Unlike a computer virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer.