1. Right Answer: C
Explanation: Immunizers defend against malware by appending sections of themselves to files '' sometime in the same way Malware append themselves. Immunizers continuously check a file for changes and report changes as possible malware behavior. Other type of Immunizers are focused to a specific malware and work by giving the malware the impression that the malware has already infected to the computer. This method is not always practical since it is not possible to immunize file against all known malware.For your exam you should know below mentioned different kinds of malware ControlsA. Scanners- Look for sequences of bit called signature that are typical malware programs.The two primary types of scanner are1. Malware mask or Signatures '' Anti-malware scanners check files, sectors and system memory for known and new (unknown to scanner) malware, on the basis of malware masks or signatures. Malware masks or signature are specific code strings that are recognized as belonging to malware. For polymorphic malware, the scanner sometimes has algorithms that check for all possible combinations of a signature that could exist in an infected file.2. Heuristic Scanner '' Analyzes the instructions in the code being scanned and decide on the basis of statistical probabilities whether it could contain malicious code. Heuristic scanning result could indicate that malware may be present, that is possibly infected. Heuristic scanner tend to generate a high level false positive errors (they indicate that malware may be present when, in fact, no malware is present)Scanner examines memory disk- boot sector, executables, data files, and command files for bit pattern that match a known malware. Scanners, therefore, need to be updated periodically to remain effective.B. Immunizers '' Defend against malware by appending sections of themselves to files '' sometime in the same way Malware append themselves. Immunizers continuously check a file for changes and report changes as possible malware behavior. Other type of Immunizers are focused to a specific malware and work by giving the malware the impression that the malware has already infected to the computer. This method is not always practical since it is not possible to immunize file against all known malware.C. Behavior Blocker- Focus on detecting potential abnormal behavior such as writing to the boot sector or the master boot record, or making changes to executable files. Blockers can potentially detect malware at an early stage. Most hardware based anti-malware mechanism are based on this concept.D. Integrity CRC checker- Compute a binary number on a known malware free program that is then stored in a database file. The number is called CyclicRedundancy Check (CRC). On subsequent scans, when that program is called to execute, it checks for changes to the file as compare to the database and report possible infection if changes have occurred. A match means no infection; a mismatch means change in the program has occurred. A change in the program could mean malware within it. These scanners are effective in detecting infection; however, they can do so only after infection has occurred. Also, a CRC checker can only detect subsequent changes to files, because they assume files are malware free in the first place. Therefore, they are ineffective against new files that are malware infected and that are not recorded in the database. Integrity checker take advantage of the fact that executable programs and boot sectors do not change often, if at all.E. Active Monitors '' Active monitors interpret DOS and read-only memory (ROM) BIOS calls, looking for malware like actions. Active monitors can be problematic because they can not distinguish between a user request and a program or a malware request. As a result, users are asked to confirm actions, including formatting a disk or deleting a file or set of files.The following were incorrect answers:Scanners -Look for sequences of bit called signature that are typical malware programs.Active Monitors '' Active monitors interpret DOS and read-only memory (ROM) BIOS calls, looking for malware like actions. Active monitors can be problematic because they can not distinguish between a user request and a program or a malware request. As a result, users are asked to confirm actions, including formatting a disk or deleting a file or set of files.Behavior Blocker- Focus on detecting potential abnormal behavior such as writing to the boot sector or the master boot record, or making changes to executable files. Blockers can potentially detect malware at an early stage. Most hardware based anti-malware mechanism are based on this concept.The following reference(s) were/was used to create this question:CISA review manual 2014 Page number 354 and 355

2. Right Answer: D
Explanation: The word INCORRECT is the keyword used in the question. All the terms presented in options correctly describes some type of anti-malware related activities.For your exam you should know below mentioned different kinds of malware ControlsA. Scanners Look for sequences of bit called signature that are typical malware programs.The two primary types of scanner are1. Malware mask or Signatures '' Anti-malware scanners check files, sectors and system memory for known and new (unknown to scanner) malware, on the basis of malware masks or signatures. Malware masks or signature are specific code strings that are recognized as belonging to malware. For polymorphic malware, the scanner sometimes has algorithms that check for all possible combinations of a signature that could exist in an infected file.2. Heuristic Scanner '' Analyzes the instructions in the code being scanned and decide on the basis of statistical probabilities whether it could contain malicious code. Heuristic scanning result could indicate that malware may be present, that is possibly infected. Heuristic scanner tend to generate a high level false positive errors (they indicate that malware may be present when, in fact, no malware is present)Scanner examines memory disk- boot sector, executables, data files, and command files for bit pattern that match a known malware. Scanners, therefore, need to be updated periodically to remain effective.B. Immunizers '' Defend against malware by appending sections of themselves to files '' sometime in the same way Malware append themselves. Immunizers continuously check a file for changes and report changes as possible malware behavior. Other types of Immunizers are focused to a specific malware and work by giving the malware the impression that the malware has already infected to the computer. This method is not always practical since it is not possible to immunize file against all known malware.C. Behavior Blocker- Focus on detecting potential abnormal behavior such as writing to the boot sector or the master boot record, or making changes to executable files. Blockers can potentially detect malware at an early stage. Most hardware based anti-malware mechanism are based on this concept.D. Integrity CRC checker- Compute a binary number on a known malware free program that is then stored in a database file. The number is called CyclicRedundancy Check (CRC). On subsequent scans, when that program is called to execute, it checks for changes to the file as compare to the database and report possible infection if changes have occurred. A match means no infection; a mismatch means change in the program has occurred. A change in the program could mean malware within it. These scanners are effective in detecting infection; however, they can do so only after infection has occurred. Also, a CRC checker can only detect subsequent changes to files, because they assume files are malware free in the first place. Therefore, they are ineffective against new files that are malware infected and that are not recorded in the database. Integrity checker take advantage of the fact that executable programs and boot sectors do not change often, if at all.E. Active Monitors '' Active monitors interpret DOS and read-only memory (ROM) BIOS calls, looking for malware like actions. Active monitors can be problematic because they can not distinguish between a user request and a program or a malware request. As a result, users are asked to confirm actions, including formatting a disk or deleting a file or set of files.The following were incorrect answers:All of the choices presented other than one were describing Anti-Malware related activitiesThe following reference(s) were/was used to create this question:CISA review manual 2014 Page number 354 and 355

3. Right Answer: A
Explanation: The NOT is a keyword used in the question. You need to find out invalid statement about VoIP. VoIP uses packet switching and not circuit switching.For your exam you should know below information about VoIP:Voice-Over-IP -IP telephony, internet telephony, is the technology that makes it possible to have a voice conversation over the Internet or over any dedicated IP network instead of dedicated transmission lines. The protocol is used to carry the signal over the IP network are commonly referred as Voice-Over-IP (VoIP).VoIP is a technology where voice traffic is carried on top of existing data infrastructure. Sounds are digitalized into IP packets and transferred through the network layer before being decode back into the original voice.VoIP allows the elimination of circuit switching and the associated waste of bandwidth. Instead, packet switching is used, where IP packets with voice data are sent over the network only when data needs to be sent.It has advantages over traditional telephony:Unlike traditional telephony, VoIP innovation progresses at market rates rather than at the rates of multilateral committee process of the InternationalTelecommunication Union (ITU)Lower cost per call or even free calls, especially for long distance callLower infrastructure costs. Once IP infrastructure is installed, no or little additional telephony infrastructure is neededVoIP Security Issues -With the introduction of VoIP, the need for security is more important because it is needed to protect two assets '' the data and the voice.Protecting the security of conversation is vital now.In VoIP, packets are sent over the network from the user's computer or VoIP phone to similar equipment at other end. Packets may pass through several intermediate systems that are not under the control of the user's ISP.The current Internet architecture does not provide same physical wire security as phone line.The main concern of VoIP solution is that while, in the case of traditional telephones, if data system is disrupted, then the different sites of the organization could still be reached via telephone. Thus a backup communication facility should be planned for if the availability of communication is vital to organization.Another issue might arise with the fact that IP telephones and their supporting equipment require the same care and maintenance as computer system do.To enhance the protection of the telephone system and data traffic, the VoIP infrastructure should be segregated using Virtual Local Area Network (VLAN).In many cases, session border controllers (SBCs) are utilized to provide security features for VoIP traffic similar to that provided by firewalls.The following were incorrect answers:Lower cost per call or even free calls, especially for long distance call - This is a valid statement about VoIP. In fact it is an advantage of VoIP.Lower infrastructure cost - This is a valid statement and advantage of using VoIP as compare to traditional telephony system.VoIP is a technology where voice traffic is carried on top of existing data infrastructure '' This is also valid statement about VoIP.The following reference(s) were/was used to create this question:CISA review manual 2014 Page number355

4. Right Answer: D
Explanation: The NOT is a keyword used in the question. You need to find out the risks which are NOT associated with PBX. All the risk listed within the options are associated with PBX.The threat of the PBX telephone system is many, depending on the goals of these attackers, and include:Theft of service - Toll fraud, probably the most common of motives for attacker.Disclosure of Information -Data disclosed without authorization, either by deliberate actionably accident. Examples includes eavesdropping on conversation and unauthorized access to routing and address data.Data Modification -Data altered in some meaningful way by recording, deleting or modifying it. For example, an intruder may change billing information or modify system table to gain additional services.Unauthorized access '' Actions that permit an unauthorized user to gain access to system resources or privileges.Denial of service -Actions that prevent the system from functioning in accordance with its intended purpose. A piece of equipment or entity may be rendered inoperable or forced to operate in a degraded state; operations that depend on timeliness may be delayed.Traffic Analysis '' A form of passive attack in which an intruder observes information about calls and make inferences, e.g. from the source and destination number or frequency and length of messages. For example, an intruder observes a high volume of calls between a company's legal department and patent office, and conclude that a patent is being filed.The following were incorrect answers:All the risks presented in options are associated with PBX. So other options are not valid.The following reference(s) were/was used to create this question:CISA review manual 2014 Page number356

5. Right Answer: A
Explanation: A Private Branch Exchange(PBX) is a sophisticated computer based switch that can be thought of as essentially a small in-house phone company for the organization that operates it. Protection of PBX is thus a height priority. Failure to secure PBX can result in exposing the organization to toll fraud, theft of proprietary or confidential information, loss of revenue or legal entanglements.PBX environment involves many security risks, presented by people both internal and external to an organization. The threat of the PBX telephone system is many, depending on the goals of these attackers, and include:Theft of service - Toll fraud, probably the most common of motives for attacker.Disclosure of Information -Data disclosed without authorization, either by deliberate actionably accident. Examples includes eavesdropping on conversation and unauthorized access to routing and address data.Data Modification -Data altered in some meaningful way by recording, deleting or modifying it. For example, an intruder may change billing information or modify system table to gain additional services.Unauthorized access '' Actions that permit an unauthorized user to gain access to system resources or privileges.Denial of service -Actions that prevent the system from functioning in accordance with its intended purpose. A piece of equipment or entity may be rendered inoperable or forced to operate in a degraded state; operations that depend on timeliness may be delayed.Traffic Analysis '' A form of passive attack in which an intruder observes information about calls and make inferences, e.g. from the source and destination number or frequency and length of messages. For example, an intruder observes a high volume of calls between a company's legal department and patent office, and conclude that a patent is being filed.The following were incorrect answers:Virtual Local Area Network - A virtual local area network (VLAN) is a logical group of workstations, servers and network devices that appear to be on the sameLAN despite their geographical distribution. A VLAN allows a network of computers and users to communicate in a simulated environment as if they exist in a single LAN and are sharing a single broadcast and multicast domain. VLANs are implemented to achieve scalability, security and ease of network management and can quickly adapt to change in network requirements and relocation of workstations and server nodes.Voice over IP - VoIP is a technology where voice traffic is carried on top of existing data infrastructure. Sounds are digitalized into IP packets and transferred through the network layer before being decode back into the original voice.Dial-up connection - Dial-up refers to an Internet connection that is established using a modem. The modem connects the computer to standard phone lines, which serve as the data transfer medium. When a user initiates a dial-up connection, the modem dials a phone number of an Internet Service Provider (ISP) that is designated to receive dial-up calls. The ISP then establishes the connection, which usually takes about ten seconds and is accompanied by several beeping an buzzing sounds.The following reference(s) were/was used to create this question:CISA review manual 2014 Page number 356