Chapter 3 Flashcards
What is the final step in authorizing a system for use in an environment?
A. Certification
B. Security evaluation and rating
C. Accreditation
D. Verification
C. Certification is a technical review of a product, and accreditation is management’s formal approval of the findings of the certification process. This question asked you which step was the final step in authorizing a system before it is used in an environment, and that is what accreditation is all about.
What feature enables code to be executed without the usual security checks?
A. Temporal isolation
B. Maintenance hook
C. Race conditions
D. Process multiplexing
B. Maintenance hooks get around the system’s or application’s security and access control checks by allowing whoever knows the key sequence to access the application and most likely its code. Maintenance hooks should be removed from any code before it gets into production.
If a component fails, a system should be designed to do which of the following?
A. Change to a protected execution domain
B. Change to a problem state
C. Change to a more secure state
D. Release all data held in volatile memory
C. The state machine model dictates that a system should start up securely, carry out secure state transitions, and even fail securely. This means that if the system encounters something it deems unsafe, it should change to a more secure state for self-preservation and protection.
The trusted computing base (TCB) contains which of the following?
A. All trusted processes and software components
B. All trusted security policies and implementation mechanisms
C. All trusted software and design mechanisms
D. All trusted software and hardware components
D. The TCB contains and controls all protection mechanisms within the system, whether they are software, hardware, or firmware.
What is the imaginary boundary that separates components that maintain security from components that are not security related?
A. Reference monitor
B. Security kernel
C. Security perimeter
D. Security policy
C. The security perimeter is a boundary between items that are within the TCB and items that are outside the TCB. It is just a mark of delineation between these two groups of items.
What is the best description of a security kernel from a security point of view?
A. Reference monitor
B. Resource manager
C. Memory mapper
D. Security perimeter
A. The security kernel is a portion of the operating system’s kernel and enforces the rules outlined in the reference monitor. It is the enforcer of the rules and is invoked each time a subject makes a request to access an object.
In secure computing systems, why is there a logical form of separation used between processes?
A. Processes are contained within their own security domains so each does not make unauthorized accesses to other processes or their resources.
B. Processes are contained within their own security perimeter so they can only access protection levels above them.
C. Processes are contained within their own security perimeter so they can only access protection levels equal to them.
D. The separation is hardware and not logical in nature.
A. Processes are assigned their own variables, system resources, and memory segments, which make up their domain. This is done so they do not corrupt each other’s data or processing activities.
What type of rating is used within the Common Criteria framework?
A. PP
B. EPL
C. EAL
D. A–D
C. The Common Criteria uses a different assurance rating system than the previously used criteria. It has packages of specifications that must be met for a product to obtain the corresponding rating. These ratings and packages are called Evaluation Assurance Levels (EALs). Once a product achieves any type of rating, customers can view this information on an Evaluated Products List (EPL).
Which of the following is a true statement pertaining to memory addressing?
A. The CPU uses absolute addresses. Applications use logical addresses. Relative addresses are based on a known address and an offset value.
B. The CPU uses logical addresses. Applications use absolute addresses. Relative addresses are based on a known address and an offset value.
C. The CPU uses absolute addresses. Applications use relative addresses. Logical addresses are based on a known address and an offset value.
D. The CPU uses absolute addresses. Applications use logical addresses. Absolute addresses are based on a known address and an offset value.
A. The physical memory addresses that the CPU uses are called absolute addresses. The indexed memory addresses that software uses are referred to as logical addresses. A relative address is a logical address that incorporates the correct offset value.
Pete is a new security manager at a financial institution that develops its own internal software for specific proprietary functionality. The financial institution has several locations distributed throughout the world and has bought several individual companies over the last ten years, each with its own heterogeneous environment. Since each purchased company had its own unique environment, it has been difficult to develop and deploy internally developed software in an effective manner that meets all the necessary business unit requirements. Which of the following best describes a standard that Pete should ensure the software development team starts to implement so that various business needs can be met?
A. ISO/IEC/IEEE 42010
B. Common Criteria
C. ISO/IEC 43010
D. ISO/IEC 15408
A. ISO/IEC/IEEE 42010 is an international standard that outlines specifications for system architecture frameworks and architecture languages. It allows for systems to be developed in a manner that addresses all of the stakeholder’s concerns.
Which of the following is an incorrect description pertaining to the common components that make up computer systems?
i. General registers are commonly used to hold temporary processing data, while special registers are used to hold process-characteristic data as in condition bits.
ii. A processor sends a memory address and a “read” request down an address bus and a memory address and a “write” request down an I/O bus.
iii. Process-to-process communication commonly takes place through memory stacks, which are made up of individually addressed buffer locations.
iv. A CPU uses a stack return pointer to keep track of the next instruction sets it needs to process.
A. i
B. i, ii
C. ii, iii
D. ii, iv
D. A processer sends a memory address and a “read” request down an address bus. The system reads data from that memory address and puts the requested data on the data bus. A CPU uses a program counter to keep track of the memory addresses containing the instruction sets it needs to process in sequence. A stack pointer is a component used within memory stack communication processes. An I/O bus is used by a peripheral device.
Mark is a security administrator who is responsible for purchasing new computer systems for a co-location facility his company is starting up. The company has several time-sensitive applications that require extensive processing capabilities. The co-location facility is not as large as the main facility, so it can only fit a smaller number of computers, which still must carry the same processing load as the systems in the main building. Which of the following best describes the most important aspects of the products Mark needs to purchase for these purposes?
A. Systems must provide symmetric multiprocessing capabilities and virtualized environments.
B. Systems must provide asymmetric multiprocessing capabilities and virtualized environments.
C. Systems must provide multiprogramming multiprocessing capabilities and virtualized environments.
D. Systems must provide multiprogramming multiprocessing capabilities and symmetric multiprocessing environments.
B. When systems provide asymmetric multiprocessing, this means multiple CPUs can be used for processing. Asymmetric indicates the capability of assigning specific applications to one CPU so that they do not have to share computing capabilities with other competing processes, which increases performance. Since a smaller number of computers can fit in the new location, virtualization should be deployed to allow for several different systems to share the same physical computer platforms.
Tom is a new security manager who is responsible for reviewing the current software that the company has developed internally. He finds that some of the software is outdated, which causes performance and functionality issues. During his testing procedures he sees that when one program stops functioning, it negatively affects other programs on the same system. He also finds out that as systems run over a period of a month, they start to perform more slowly, but by rebooting the systems this issue goes away.
- Which of the following best describes a characteristic of the software that may be causing issues?
A. Cooperative multitasking
B. Preemptive multitasking
C. Maskable interrupt use
D. Nonmaskable interrupt use
A. Cooperative multitasking means that a developer of an application has to properly code his software to release system resources when the application is finished using them, or the other software running on the system could be negatively affected. In this type of situation an application could be poorly coded and not release system resources, which would negatively affect other software running on the system. In a preemptive multitasking environment, the operating system would have more control of system resource allocation and provide more protection for these types of situations.
Tom is a new security manager who is responsible for reviewing the current software that the company has developed internally. He finds that some of the software is outdated, which causes performance and functionality issues. During his testing procedures he sees that when one program stops functioning, it negatively affects other programs on the same system. He also finds out that as systems run over a period of a month, they start to perform more slowly, but by rebooting the systems this issue goes away.
Which of the following best describes why rebooting helps with system performance in the situation described in this scenario?
A. Software is not using cache memory properly.
B. Software is carrying out too many mode transitions.
C. Software is working in ring 0.
D. Software is not releasing unused memory.
D. When software is poorly written, it could be allocating memory and not properly releasing it. This can affect the performance of the whole system, since all software processes have to share a limited supply of memory. When a system is rebooted, the memory allocation constructs are reset.
Steve has found out that the software product that his team submitted for evaluation did not achieve the actual rating they were hoping for. He was confused about this issue since the software passed the necessary certification and accreditation processes before being deployed. Steve was told that the system allows for unauthorized device drivers to be loaded and that there was a key sequence that could be used to bypass the software access control protection mechanisms. Some feedback Steve received from the product testers is that it should implement address space layout randomization and data execution protection.
Which of the following best describes Steve’s confusion?
A. Certification must happen first before the evaluation process can begin.
B. Accreditation is the acceptance from management, which must take place before the evaluation process.
C. Evaluation, certification, and accreditation are carried out by different groups with different purposes.
D. Evaluation requirements include certification and accreditation components.
C. Evaluation, certification, and accreditation are carried out by different groups with different purposes. Evaluations are carried out by qualified third parties who use specific evaluation criteria (e.g., Common Criteria) to assign an assurance rating to a tested product. A certification process is a technical review commonly carried out internally to an organization, and accreditation is management’s formal acceptance that is carried out after the certification process. A system can be certified internally by a company and not pass an evaluation testing process because they are completely different things.
Steve has found out that the software product that his team submitted for evaluation did not achieve the actual rating they were hoping for. He was confused about this issue since the software passed the necessary certification and accreditation processes before being deployed. Steve was told that the system allows for unauthorized device drivers to be loaded and that there was a key sequence that could be used to bypass the software access control protection mechanisms. Some feedback Steve received from the product testers is that it should implement address space layout randomization and data execution protection.
Which of the following best describes an item the software development team needs to address to ensure that drivers cannot be loaded in an unauthorized manner?
A. Improved security kernel processes
B. Improved security perimeter processes
C. Improved application programming interface processes
D. Improved garbage collection processes
A. If device drivers can be loaded improperly, then either the access control rules outlined within the reference monitor need to be improved upon or the current rules need to be better enforced through the security kernel processes. Only authorized subjects should be able to install sensitive software components that run within ring 0 of a system.
Steve has found out that the software product that his team submitted for evaluation did not achieve the actual rating they were hoping for. He was confused about this issue since the software passed the necessary certification and accreditation processes before being deployed. Steve was told that the system allows for unauthorized device drivers to be loaded and that there was a key sequence that could be used to bypass the software access control protection mechanisms. Some feedback Steve received from the product testers is that it should implement address space layout randomization and data execution protection.
Which of the following best describes some of the issues that the evaluation testers most likely ran into while testing the submitted product?
A. Nonprotected ROM sections
B. Vulnerabilities that allowed malicious code to execute in protected memory sections
C. Lack of a predefined and implemented trusted computing base
D. Lack of a predefined and implemented security kernel
B. If testers suggested to the team that address space layout randomization and data execution protection should be integrated, this is most likely because the system allows for malicious code to easily execute in memory sections that would be dangerous to the system. These are both memory protection approaches.
John has been told that one of the applications installed on a web server within the DMZ accepts any length of information that a customer using a web browser inputs into the form the web server provides to collect new customer data. Which of the following describes an issue that John should be aware of pertaining to this type of vulnerability?
A. Application is written in the C programming language.
B. Application is not carrying out enforcement of the trusted computing base.
C. Application is running in ring 3 of a ring-based architecture.
D. Application is not interacting with the memory manager properly.
A. The C language is susceptible to buffer overflow attacks because it allows for direct pointer manipulations to take place. Specific commands can provide access to low-level memory addresses without carrying out bounds checking.
What is the goal of cryptanalysis?
A. To determine the strength of an algorithm
B. To increase the substitution functions in a cryptographic algorithm
C. To decrease the transposition functions in a cryptographic algorithm
D. To determine the permutations used
A. Cryptanalysis is the process of trying to reverse-engineer a cryptosystem, with the possible goal of uncovering the key used. Once this key is uncovered, all other messages encrypted with this key can be accessed. Cryptanalysis is carried out by the white hats to test the strength of the algorithm.
