CISSP Exam Dumps - Certified Information Systems Security Professional (CISSP)

The residual risk is 25% in this scenario. Residual risk is the portion of risk that remains after security measures have been applied to mitigate the risk. Residual risk can be calculated by subtracting the risk reduction from the total risk. In this scenario, the total risk is 100%, and the risk reduction is 75%. The risk reduction is 75% because the control stops 50% of attacks, and reduces the impact of an attack by 50%. Therefore, the residual risk is 100% - 75% = 25%. Alternatively, the residual risk can be calculated by multiplying the probability and the impact of the remaining risk. In this scenario, the probability of an attack is 50%, and the impact of an attack is 50%. Therefore, the residual risk is 50% x 50% = 25%. 50%, 75%, and 100% are not the correct answers to the question, as they do not reflect the correct calculation of the residual risk. 

The most important part of an awareness and training plan to prepare employees for emergency situations is to design business continuity and disaster recovery training programs for different audiences. This means that the training content, format, frequency, and delivery methods should be tailored to the specific needs, roles, and responsibilities of the target audience, such as senior management, business unit managers, IT staff, recovery team members, or general employees. Different audiences may have different levels of awareness, knowledge, skills, and involvement in the business continuity and disaster recovery processes, and therefore require different types of training to ensure they are adequately prepared and informed. Designing business continuity and disaster recovery training programs for different audiences can help to increase the effectiveness, efficiency, and consistency of the training, as well as the engagement, motivation, and retention of the learners. Having emergency contacts established for the general employee population to get information, conducting business continuity and disaster recovery training for those who have a direct role in the recovery, and publishing a corporate business continuity and disaster recovery plan on the corporate website are all important parts of an awareness and training plan, but they are not as important as designing business continuity and disaster recovery training programs for different audiences. Having emergency contacts established for the general employee population to get information can help to provide timely and accurate communication and guidance during an emergency situation, but it does not necessarily prepare the employees for their roles and responsibilities before, during, and after the emergency. Conducting business continuity and disaster recovery training for those who have a direct role in the recovery can help to ensure that they are competent and confident to perform their tasks and duties in the event of a disruption, but it does not address the needs and expectations of other audiences who may also be affected by or involved in the business continuity and disaster recovery processes. Publishing a corporate business continuity and disaster recovery plan on the corporate website can help to make the plan accessible and transparent to the stakeholders, but it does not guarantee that the plan is understood, followed, or updated by the employees. 

The most appropriate action when reusing media that contains sensitive data is to sanitize the media. Sanitization is the process of removing or destroying all data from the media in such a way that it cannot be recovered by any means. Sanitization can be achieved by various methods, such as overwriting, degaussing, or physical destruction. Sanitization ensures that the sensitive data is not exposed or compromised when the media is reused or disposed of. Erase, encrypt, and degauss are not the most appropriate actions when reusing media that contains sensitive data, although they may be related or useful steps. Erase is the process of deleting data from the media by using the operating system or application commands or functions. Erase does not guarantee that the data is completely removed from the media, as it may leave traces or remnants that can be recovered by using special tools or techniques. Encrypt is the process of transforming data into an unreadable form by using a cryptographic algorithm and a key. Encrypt can protect the data from unauthorized access or disclosure, but it does not remove the data from the media. Encrypt also requires that the key is securely managed and stored, and that the encryption algorithm is strong and reliable. Degauss is the process of applying a strong magnetic field to the media to erase or scramble the data. Degauss can effectively sanitize magnetic media, such as hard disks or tapes, but it does not work on optical media, such as CDs or DVDs. Degauss also renders the media unusable, as it destroys the servo tracks and the firmware that are needed for the media to function properly. 

The most appropriate measure to implement when a group of system administrators must share a high-level access set of credentials due to system constraints is a credential check-out process for a per-use basis. This means that the system administrators must request and obtain the credentials from a secure source each time they need to use them, and return them after they finish their tasks. This can help to reduce the risk of unauthorized access, misuse, or compromise of the credentials, as well as to enforce accountability and traceability of the system administrators’ actions. Increasing console lockout times, reducing the group size, and enabling full logging are not as effective as a credential check-out process, as they do not address the root cause of the problem, which is the sharing of the credentials. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 5: Security Engineering, page 633; Official (ISC)2 Guide to the CISSP CBK, Fifth Edition, Chapter 3: Security Architecture and Engineering, page 412.

The security accreditation task of the System Development Life Cycle (SDLC) process is completed at the end of the system implementation phase. The SDLC is a framework that describes the stages and activities involved in the development, deployment, and maintenance of a system. The SDLC typically consists of the following phases: system initiation, system acquisition and development, system implementation, system operations and maintenance, and system disposal. The security accreditation task is the process of formally authorizing a system to operate in a specific environment, based on the security requirements, controls, and risks. The security accreditation task is part of the security certification and accreditation (C&A) process, which also includes the security certification task, which is the process of technically evaluating and testing the security controls and functionality of a system. The security accreditation task is completed at the end of the system implementation phase, which is the phase where the system is installed, configured, integrated, and tested in the target environment. The security accreditation task involves reviewing the security certification results and documentation, such as the security plan, the security assessment report, and the plan of action and milestones, and making a risk-based decision to grant, deny, or conditionally grant the authorization to operate (ATO) the system. The security accreditation task is usually performed by a senior official, such as the authorizing official (AO) or the designated approving authority (DAA), who has the authority and responsibility to accept the security risks and approve the system operation. The security accreditation task is not completed at the end of the system acquisition and development, system operations and maintenance, or system initiation phases. The system acquisition and development phase is the phase where the system requirements, design, and development are defined and executed, and the security controls are selected and implemented. The system operations and maintenance phase is the phase where the system is used and supported in the operational environment, and the security controls are monitored and updated. The system initiation phase is the phase where the system concept, scope, and objectives are established, and the security categorization and planning are performed. 

Unused space in a disk cluster is important in media analysis because it may contain residual data that has not been overwritten. A disk cluster is a fixed-length block of disk space that is used to store files. A file may occupy one or more clusters, depending on its size. If a file is smaller than a cluster, the remaining space in the cluster is called slack space. If a file is deleted, the clusters that were allocated to the file are marked as free or unallocated, but the data in the clusters is not erased. Residual data is the data that remains in the slack space or the unallocated space after a file is created, modified, or deleted. Residual data is important in media analysis because it may contain valuable or sensitive information that can be recovered by using forensic tools or techniques. Residual data may include fragments of previous files, temporary files, cache files, swap files, metadata, passwords, encryption keys, or personal data. Residual data can pose a security risk if the media is reused, recycled, or disposed of without proper sanitization. Hidden viruses and Trojan horses, information about the File Allocation table (FAT), and information about patches and upgrades to the system are not the reasons why unused space in a disk cluster is important in media analysis, although they may be related or relevant concepts. Hidden viruses and Trojan horses are malicious programs that can infect or compromise a system or a network. Hidden viruses and Trojan horses may reside in the unused space in a disk cluster, but they are not the result of file creation, modification, or deletion, and they are not the target of media analysis. Information about the File Allocation table (FAT) is the information that describes how the disk clusters are allocated to the files. Information about the File Allocation table (FAT) is stored in a special area of the disk, not in the unused space in a disk cluster, and it is not the result of file creation, modification, or deletion, and it is not the target of media analysis. Information about patches and upgrades to the system is the information that describes the changes or improvements made to the system software or hardware. Information about patches and upgrades to the system may be stored in the unused space in a disk cluster, but it is not the result of file creation, modification, or deletion, and it is not the target of media analysis. 

A DoS attack on a syslog server exploits weakness in TCP and UDP protocols. A syslog server is a server that collects and stores log messages from various devices on a network, such as routers, switches, firewalls, or servers. A syslog server uses either TCP or UDP protocols to receive log messages from the devices. A DoS attack on a syslog server can exploit the weakness of these protocols by sending a large volume of fake or malformed log messages to the syslog server, causing it to crash or become unresponsive. The other protocols are not relevant to a syslog server or a DoS attack. References: Denial-of-Service Attacks: History, Techniques & Prevention; What is a syslog server? | SolarWinds MSP.

An application proxy provides the most comprehensive filtering of Peer-to-Peer (P2P) traffic. P2P traffic is a type of network traffic that involves direct communication and file sharing between peers, without the need for a central server. P2P traffic can be used for legitimate purposes, such as distributed computing, content delivery, or collaboration, but it can also be used for illegal or malicious purposes, such as piracy, malware distribution, or denial-of-service attacks. P2P traffic can also consume a lot of bandwidth and degrade the performance of other network applications. Therefore, it may be desirable to filter or block P2P traffic on a network. An application proxy is a type of firewall that operates at the application layer of the OSI model, and acts as an intermediary between the client and the server. An application proxy can inspect the content and the behavior of the network traffic, and apply granular filtering rules based on the specific application protocol, such as HTTP, FTP, or SMTP. An application proxy can also perform authentication, encryption, caching, and logging functions. An application proxy can provide the most comprehensive filtering of P2P traffic, as it can identify and block the P2P applications and protocols, regardless of the port number or the payload. An application proxy can also prevent P2P traffic from bypassing the firewall by using encryption or tunneling techniques. The other options are not as effective as an application proxy for filtering P2P traffic. A port filter is a type of firewall that operates at the transport layer of the OSI model, and blocks or allows traffic based on the source and destination port numbers. A port filter cannot inspect the content or the behavior of the traffic, and cannot distinguish between different applications that use the same port number. A port filter can also be easily evaded by P2P traffic that uses random or well-known port numbers, such as port 80 for HTTP. A network boundary router is a router that connects a network to another network, such as the Internet. A network boundary router can perform some basic filtering functions, such as access control lists (ACLs) or packet filtering, but it cannot inspect the content or the behavior of the traffic, and cannot apply granular filtering rules based on the specific application protocol. A network boundary router can also be easily evaded by P2P traffic that uses encryption or tunneling techniques. An access layer switch is a switch that connects end devices, such as PCs, printers, or servers, to the network. An access layer switch can perform some basic filtering functions, such as MAC address filtering or port security, but it cannot inspect the content or the behavior of the traffic, and cannot apply granular filtering rules based on the specific application protocol. An access layer switch can also be easily evaded by P2P traffic that uses encryption or tunneling techniques. References: Why and how to control peer-to-peer traffic | Network World; Detection and Management of P2P Traffic in Networks using Artificial Neural Networksa | Journal of Network and Systems Management; Blocking P2P And File Sharing - Cisco Meraki Documentation.