A collision is when the hash value of two different data from one hash function is the same. Hashing is one-way cryptography, which means that the original plaintext is no longer known to be one or the other.

〇：TOC/TOU

Certain attacks can take advantage of the way a system processes requests and performs tasks. A TOC/TOU attack handles a series of steps that the system uses to complete a task. This type of attack takes advantage of the reliance on the timing of events occurring in a multitasking operating system; TOC/TOU is a software vulnerability that allows the use of condition checking (i.e., credential verification) and the results from that condition checking function. In the scenario in this question, the fact that the web application is likely correctly configured indicates that the programming code of this application has this type of vulnerability embedded in the code itself.

×：Buffer overflow

When too much data is accepted as input to a particular process, a buffer overflow occurs. This is incorrect because it does not match the event in the problem statement. A buffer is an allocated segment of memory. A buffer can overflow arbitrarily with too much data, but to be used by an attacker, the code inserted into the buffer must be of a specific length and require a command to be executed by the attacker. These types of attacks are usually exceptional in that the fault is segmented, or sensitive data is provided to the attacker.

×：Blind SQL Injection

Blind SQL injection attacks are wrong because they are a type of SQL injection attack that sends true or false questions to the database. In a basic SQL injection, the attacker sends specific instructions in SQL format to query the associated database. In a blind SQL attack, the attacker is limited to sending a series of true-false questions to the database in order to analyze the database responses and gather sensitive information.

×：Cross Site Request Forgery (CSRF)

Cross Site Request Forgery (CSRF) is incorrect because it is an attack type that attempts to trick the victim into loading a web page containing malicious requests or operations. The attack operation is performed within the context of the victim’s access rights. The request inherits the victim’s identity and performs undesirable functions for the victim. In this type of attack, the attacker can cause the victim’s system to perform unintended actions such as changing account information, retrieving account data, or logging out. This type of attack could be related to the scenario described in this question, but focuses on how the user can bypass the locking mechanism built into the web application. The logic in the programming code is incorrectly developed and the locking function is bypassed because a rigorous series of checks and usage sequences are not performed correctly.

〇：Graham-Denning Model

The Graham-Denning model addresses how access rights between subjects and objects are defined, developed, and integrated. It defines a basic set of rights in terms of the commands that a particular subject can execute on an object. The model has eight basic protective rights or rules on how to safely perform these types of functions

×：Brewer-Nash Model

It is incorrect because its purpose is to provide access control that can be changed dynamically according to the user’s previous actions. The main purpose is to protect against conflicts of interest due to user access attempts. For example, if a large marketing firm provides marketing promotions and materials for two banks, the employee responsible for the Bank A project should not be able to see information about Bank B, the marketing firm’s other bank customer. A conflict of interest could arise because the banks are competitors. If the project manager of the marketing firm’s Project A can see information about Bank B’s new marketing campaign, he may attempt to execute it rather than promote it to please more direct customers. Marketing firms have a bad reputation when internal employees can act irresponsibly.

×：Clark-Wilson Model

The Clark-Wilson model is incorrect because it is implemented to protect data integrity and ensure that transactions are properly formatted within the application. Subjects can only access objects through authorized programs. Segregation of duties is enforced. Auditing is required. The Clark-Wilson model addresses three integrity goals: preventing changes by unauthorized users, preventing inappropriate changes by unauthorized users, and maintaining internal and external consistency.

×：Bell-LaPadula Model

This model was developed to address concerns about the security of U.S. military systems and the leakage of classified information, and is incorrect. The primary goal of the model is to prevent unauthorized access to classified information. It is a state machine model that enforces the confidentiality aspect of access control. Matrices and security levels are used to determine if a subject has access to different objects. Specific rules are applied to control how objects interact with each other compared to the subject’s object classification.

〇：TOGAF

The Open Group Architecture Framework (TOGAF) is a vendor-independent platform for the development and implementation of enterprise architecture. It focuses on the effective management of enterprise data using metamodels and service-oriented architectures (SOA). Proficient implementations of TOGAF aim to reduce fragmentation caused by inconsistencies between traditional IT systems and actual business processes. It also coordinates new changes and functionality so that new changes can be easily integrated into the enterprise platform.

×：Department of Defense Architecture Framework (DoDAF)

In accordance with the guidelines for the organization of the enterprise architecture of the U.S. Department of Defense systems, this is incorrect. It is also suitable for large, complex integrated systems in the military, civilian, and public sectors.

×：Capability Maturity Model Integration (CMMI) during software development.

It is inappropriate because it is a framework for the purpose of designing and further improving software. CMMI provides a standard for software development processes that can measure the maturity of the development process.

×：ISO/IEC 42010

Incorrect because it consists of recommended practices to simplify the design and conception of software-intensive system architectures. This standard provides a kind of language (terminology) to describe the different components of software architecture and how to integrate it into the development life cycle.

〇：Known Plaintext Attacks

A known-plaintext attack is a situation in which a decryptor can obtain plaintext indiscriminately. A ciphertext-alone attack is a situation where a decryptor can acquire ciphertext indiscriminately. A known-plaintext attack acquires the plaintext but does not know what ciphertext it is paired with, meaning that decryption is attempted with only two random ciphertexts. In this situation, it is difficult to decrypt. Therefore, the correct answer is “known-plaintext attack.

×：Selective Plaintext Attack

A choice-plaintext attack is a situation in which the decryptor can freely choose the plaintext to acquire and obtain the ciphertext.

×：Adaptive Choice Plaintext Attack

An adaptive choice-plaintext attack is a situation in which the decryptor can freely choose which plaintext to acquire and acquire the ciphertext, and can repeat the acquisition again after seeing the result.

×：None of the above

It is rare for the answer to be “none of the above” when the choice is “most of the above.

〇：Increased Processing Power

The increased processing power of personal computers and servers has increased the probability of successful brute force and cracking attacks against security mechanisms that were not feasible a few years ago. Today’s processors can execute an incredible number of instructions per second. These instructions can be used to break passwords, encryption keys, or direct malicious packets to be sent to the victim’s system.

×：Increased circuitry, cache memory, and multiprogramming

This is incorrect because an increase does not make a particular type of attack more powerful. Multiprogramming means loading multiple programs or processes into memory at the same time. It allows antivirus software, word processors, firewalls, and e-mail clients to run simultaneously. Cache memory is a type of memory used for fast write and read operations. If the system expects that the program logic will need to access certain information many times during processing, the information is stored in cache memory for easy and quick access.

×：Dual-mode computation

The answer is not specific and does not measure conformance to the problem. When examining microprocessor advances, there is no actual dual-mode calculation.

×：Direct Memory Access I/O

Incorrect because this method transfers instructions and data between I/O (input/output) devices and the system’s memory without using the CPU. Direct Memory Access I/O significantly increases data transfer speed.

In an asymmetric algorithm, every user must have at least one key pair (private and public key). In a public key system, each entity has a separate key. The formula for determining the number of keys needed in this environment is by the number N × 2, where N is the number of people to distribute. In other words, 260 x 2 = 520. Therefore, the correct answer is 520.

〇：One-time pad

Stream ciphers refer to one-time pad technology. In practice, stream ciphers cannot provide the level of protection that one-time pads do, but are practical.

×：AES

AES is incorrect because it is a symmetric block cipher. When a block cipher is used for encryption and decryption purposes, the message is divided into blocks of bits.

×：Block ciphers

Block ciphers are used for encryption and decryption purposes. The message is wrong because it is divided into blocks of bits.

×：RSA

RSA is incorrect because it is an asymmetric algorithm.

The Kerckhoffs’s principle is the idea that cryptography should be secure even if everything but the private key is known. When encrypting data, one decides on a private key and how to encrypt it using that private key. Kerckhoffs says that even if it is known how it is encrypted, it should not be deciphered as long as the secret key is not discovered. Encryption has been with the history of human warfare. The main purpose is to communicate a strategy to one’s allies without being discovered by the enemy. In battle, its designs and encryption devices may be stolen by spies. Therefore, the encryption must be such that it cannot be solved without the key, no matter how much is known about how it works.

〇：Keys will need to be distributed via a secure transmission channel.

For two users to exchange messages encrypted with a symmetric algorithm, they need to figure out how to distribute the key first. If the key is compromised, all messages encrypted with that key can be decrypted and read by an intruder. Simply sending the key in an email message is not secure because the key is not protected and can easily be intercepted and used by an attacker.

×：Computation is more intensive than in asymmetric systems.

That is incorrect because it describes the advantages of symmetric algorithms. Symmetric algorithms tend to be very fast because they are less computationally intensive than asymmetric algorithms. They can encrypt and decrypt relatively quickly large amounts of data that take an unacceptable amount of time to encrypt and decrypt with asymmetric algorithms.

×：Much faster operation than asymmetric systems

Symmetric algorithms are faster than asymmetric systems, but this is an advantage. Therefore, it is incorrect.

×：Mathematically intensive tasks must be performed

Asymmetric algorithms are wrong because they perform a mathematically intensive task. Symmetric algorithms, on the other hand, perform relatively simple mathematical functions on bits during the encryption and decryption process.

〇：Primary entry doors should have controlled access via swipe card or cryptographic locks. Secondary doors should not be secured from the inside and allowed entry. 

Data centers, server rooms, and wiring closets should be located in the core areas of the facility, near wiring distribution centers. Strict access control mechanisms and procedures should be implemented for these areas. Access control mechanisms can lock smart card readers, biometric readers, or a combination of these. These restricted areas should have only one access door, but fire code requirements typically dictate that there must be at least two doors in most data centers and server rooms. Only one door should be used for daily entry and exit and the other door should be used only in case of an emergency, i.e., if a fire breaks out in a data center or server room, the door should be locked. This second door should not be an access door, meaning people should not be able to come through this door. It should be locked, but should have a panic bar that will release the lock if it is used as an exit, pushed from the inside.

×：The primary and secondary entry doors must have control access via swipe cards or cryptographic locks.  

This is incorrect because even two entry doors should not be allowed to pass through with the identification, authentication, and authorization process. There should only be one entry point into the server room. No other door should provide an entry point, but can be used for an emergency exit. Therefore, secondary doors should be protected from the inside to prevent intrusion.

×：The primary entry door should have controlled access via a guard. Two doors should not be secured from the inside and allowed entry.

The main entry door to the server room is incorrect as it requires an identification, authentication, and authorization process to be performed. Swipe cards and cryptographic locks perform these functions. Server rooms should ideally not be directly accessible from public areas such as stairways, hallways, loading docks, elevators, and restrooms. This helps prevent foot traffic from casual passersby. Those who are by the door to the area to be secured should have a legitimate reason for being there, as opposed to those on the way to the meeting room, for example.

×：The main entry door must have controlled access via swipe card or crypto lock. Two doors must have security guards.  

Two doors should not have security guards, because it is wrong. The door should be protected from the inside simply so it cannot be used as an entry. Two-door must function as an emergency exit.

〇：The cloud provider is provided a platform as a service that provides a computing platform that may include an operating system, database, and web servers.

Cloud computing is a term used to describe the aggregation of network and server technologies, each virtualized, to provide customers with a specific computing environment that matches their needs. This centralized control provides end users with self-service, broad access across multiple devices, resource pooling, rapid elasticity, and service monitoring capabilities.

There are different types of cloud computing products: IaaS provides virtualized servers in the cloud; PaaS allows applications to be developed individually; SaaS allows service providers to deploy services with no development required and with a choice of functionality; and IaaS allows customers to choose the type of service they want to use. ” The term “PaaS” must fit the definition of “PaaS” because it requires that “the original application configuration remains the same”. Thus, the correct answer is, “The cloud provider provides a computing platform that may include an operating system, database, and web server, where the platform as a service is provided.” The following is the correct answer

×：The cloud provider is provided with an infrastructure as a service that provides a computing platform that can include an operating system, database, and web servers.

IaaS Description.

×：The cloud provider is provided with software services that provide an infrastructure environment similar to that of a traditional data center.

This is a description of the operational benefits of cloud computing. It is not a definition.

×：The cloud provider provides software as a service in a computing platform environment where application functionality is internalized.

SaaS Description.

〇：Conduct a risk analysis.

The first step in the procedure described, which is the first step to be taken only to deploy an effective physical security program, is to conduct a risk analysis to identify vulnerabilities and threats and to calculate the business impact of each threat. The team presents the results of the risk analysis to management to define an acceptable risk level for the physical security program. From there, the team evaluates and determines if the baseline is met by implementation. Once the team identifies its responses and implements the measures, performance is continually evaluated. These performances will be compared to the established baselines. If the baseline is maintained on an ongoing basis, the security program is successful because it does not exceed the company’s acceptable risk level.

×：Create a performance metric for the countermeasure.  

The procedure to create a countermeasure performance metric is incorrect because it is not the first step in creating a physical security program. If monitored on a performance basis, it can be used to determine how beneficial and effective the program is. It allows management to make business decisions when investing in physical security protection for the organization. The goal is to improve the performance of the physical security program, leading to a cost-effective way to reduce the company’s risk. You should establish a performance baseline and then continually evaluate performance to ensure that the firm’s protection goals are being met. Examples of possible performance metrics include: number of successful attacks, number of successful attacks, and time taken for attacks.

×：Design program.  

Designing the program is wrong because it should be done after the risk analysis. Once the level of risk is understood, then the design phase can be done to protect against the threats identified in the risk analysis. The design of deterrents, delays, detections, assessments, and responses will incorporate the necessary controls for each category of the program.

×：Implement countermeasures.  

Wrong because implementing countermeasures is one of the last steps in the process of deploying a physical security program.

〇：Common Criteria

Common Criteria was created in the early 1990s as a way to combine the strengths of both the Trustworthy Computer Systems Evaluation Criteria (TCSEC) and the Information Technology Security Evaluation Criteria (ITSEC) and eliminate their weaknesses. Common Criteria is more flexible than TCSEC and easier than ITSEC. Common Criteria is recognized worldwide and assists consumers by reducing the complexity of assessments and eliminating the need to understand the definitions and meanings of different assessments in different assessment schemes. This also helps manufacturers because they can now build a specific set of requirements when they want to market their products internationally, rather than having to meet several different evaluation criteria under different rules and requirements.

×：ITSEC

This is incorrect because it is not the most widely used information technology security evaluation standard. ITSEC was the first attempt to establish a single standard for evaluating the security attributes of computer systems and products in many European countries. In addition, ITSEC separates functionality and assurance in its evaluations, giving each a separate rating. It was developed to provide greater flexibility than TCSEC and addresses integrity, availability, and confidentiality in networked systems. The goal of ITSEC was to become the global standard for product evaluation, but it failed to achieve that goal and was replaced by Common Criteria.

×：Red Book

Wrong, as it is a U.S. government publication that addresses the topic of security evaluation of networks and network components. Formally titled Trusted Network Interpretation, it provides a framework for protecting different types of networks. Subjects accessing objects on the network must be controlled, monitored, and audited.

×：Orange Book

Incorrect as this is a U.S. Government publication that addresses government and military requirements and expectations for operating systems. The Orange Book is used to evaluate whether a product is suitable for the security characteristics and specific applications or functions required by the vendor. The Orange Book is used to review the functionality, effectiveness, and assurance of the product under evaluation, using classes designed to address typical patterns of security requirements. It provides a broad framework for building and evaluating trusted systems, with an emphasis on controlling which users have access to the system. We call it the Orange Book, but another name for it is Trusted Computer System Evaluation Criteria (TCSEC).

〇：Data Encryption

The Advanced Encryption Standard (AES) is a data encryption standard developed to improve upon the previous de facto standard, Data Encryption Standard (DES). As a symmetric algorithm, AES is used to encrypt data. Therefore, the correct answer is “data encryption.

There are other situations where AES is used in the other choices, but encrypting data is the most focused or better answer. Thus, there are cases where all of the choices are correct.

×：Data integrity

This is a characteristic of digital signatures.

×：Key recovery

It is a property of decryption and key escrow.

×：Symmetric key distribution

Using symmetric keys for AES distribution lowers the key delivery problem.

〇：All failed access attempts should be logged and reviewed.

The physical access control system may use software and auditing capabilities to generate an audit trail or access log associated with access attempts. The date and time of the entry point when access was attempted, the user ID used when access was attempted, and any failed access attempts, among others, should be recorded.

×：Failed access attempts are recorded and only security personnel are entitled to review them.

Unless someone actually reviews them, the access logs are as useless as the audit logs generated by the computer. Security guards should review these logs, but security professionals and facility managers should review these logs on a regular basis. The administrator must know the existence and location of entry points into the facility.

×：Only successful access attempts should be logged and reviewed.

Wrong, as unsuccessful access attempts should be logged and reviewed. Audit should be able to alert you to suspicious activity even though you are denying an entity access to a network, computer, or location.

×：Failed access attempts outside of business hours should be logged and reviewed.

Incorrect, as all unauthorized access attempts should be logged and reviewed regardless. Unauthorized access can occur at any time.

〇：The security kernel implements and executes the reference monitor

The Trusted Computing Base (TCB) is a complete combination of protection mechanisms for a system. These are in the form of hardware, software, and firmware. These same components also comprise the security kernel. Reference monitors are access control concepts implemented and enforced by the security kernel via hardware, software, and firmware. In doing so, it ensures that the security kernel, the subject, has the proper permissions to access the object it is requesting. The subject, be it a program, user, or process, cannot access the requesting file, program, or resource until it is proven that it has the proper access rights.

×：The reference monitor is the core of the Trusted Computing Base (TCP), which is comprised of the security kernel.

This is incorrect because the reference monitor is not the core of the TCB. The core of the TCB is the security kernel, and the security kernel implements the concepts of the reference monitor. The reference monitor is a concept about access control. It is often referred to as an “abstract machine” because it is not a physical component.

×：The reference monitor implements and executes the security kernel.

The reference monitor does not implement and execute the security kernel, which is incorrect. On the contrary, the security kernel implements and executes the reference monitor. The reference monitor is an abstract concept, while the security kernel is a combination of hardware, software, and firmware in a trusted computing base.

×：The security kernel, i.e., the abstract machine, implements the concept of a reference monitor.

This is incorrect because abstract machine is not another name for security kernel. Abstract machine is another name for the reference monitor. This concept ensures that the abstract machine acts as an intermediary between the subject and the object, ensuring that the subject has the necessary rights to access the object it is requesting and protecting the subject from unauthorized access and modification. The security kernel functions to perform these activities.

Compromise is when what used to be secure encryption becomes insecure due to the evolution of computers. Cryptography is based on the sharing of a single answer, a key, among those communicating. The key is generated by computer calculations, and a third party must solve a difficult problem that would take several years to derive. However, as the computational power of computers has evolved, it is now possible to solve difficult problems that could not be solved before. In this case, encryption is meaningless. This is the compromise caused by evolution. Therefore, the correct answer is “Compromise.

〇：Run an algorithm that identifies unused committed memory and informs the operating system that memory is available.

This answer describes the function of the garbage collector, not the memory manager. The garbage collector is a countermeasure against memory leaks. It is software that runs an algorithm to identify unused committed memory and tells the operating system to mark that memory as “available. Different types of garbage collectors work with different operating systems, programming languages, and algorithms.

In some cases, a four-choice question can be answered without knowing the exact answer; since there is only one correct answer in a four-choice question, the answers can be grouped together to reduce it to “since they are saying the same thing, it is not right that only one of them is correct, therefore they are both wrong.

There are two answers to the effect of controlling the process to handle memory appropriately, but if the memory manager does not have that functionality, both would be correct, and therefore can be eliminated from the choices in the first place.

×：If processes need to use the same shared memory segment, use complex controls to guarantee integrity and confidentiality.

If processes need to use the same shared memory segment, the memory manager uses complex controls to ensure integrity and confidentiality. This is important to protect memory and the data in it, since two or more processes can share access to the same segment with potentially different access rights. The memory manager also allows many users with different levels of access rights to interact with the same application running on a single memory segment.

×：Restrict processes to interact only with the memory segments allocated to them.

The memory manager is responsible for limiting the interaction of processes to only those memory segments allocated to them. This responsibility falls under the protection category and helps prevent processes from accessing segments to which they are not allowed. Another protection responsibility of the memory manager is to provide access control to memory segments.

×：Swap contents from RAM to hard drive as needed.

This is incorrect because swapping contents from RAM to hard drive as needed is the role of memory managers in the relocation category. When RAM and secondary storage are combined, they become virtual memory. The system uses the hard drive space to extend the RAM memory space. Another relocation responsibility is to provide pointers for applications when instructions and memory segments are moved to another location in main memory.