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.

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.

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：Digital Signature

A digital signature is a hash value encrypted with the sender’s private key. The act of signing means encrypting a hash value of a message with a private key. A message can be digitally signed, providing authentication, non-repudiation, and integrity. The hash function guarantees the integrity of the message, and the signature of the hash value provides authentication and non-repudiation.

×：Encryption Algorithms

Encryption algorithms are wrong because they provide confidentiality. Encryption is most commonly performed using symmetric algorithms. Symmetric algorithms can provide authentication, non-repudiation, and integrity as well as confidentiality.

×：Hash Algorithms

Hash algorithms are wrong because they provide data integrity. Hash algorithms generate a message digest, which detects whether modifications have been made (also called a hash value). The sender and receiver individually generate their own digests, and the receiver compares these values. If they differ, the receiver can know the message has been modified. Hash algorithms cannot provide authentication or non-repudiation.

×：Encryption paired with digital signatures

This is incorrect because encryption and digital signatures provide confidentiality, authentication, non-repudiation, and integrity. Encryption alone provides confidentiality. And digital signatures provide authentication, non-repudiation, and integrity. The question requires that it can provide authentication, non-repudiation, and integrity. It is a nasty question.

〇：Multiple processes are using the same resources.

The system uses hard drive space (called swap space) that is reserved to expand RAM memory space. When the system fills up volatile memory space, data is written from memory to the hard drive. When a program requests access to this data, it is returned from the hard drive to memory in specific units called page frames. Accessing data stored on hard drive pages takes longer than accessing data stored in memory because it requires read/write access to the physical disk. A security issue with using virtual swap space is that two or more processes can use the same resources and corrupt or damage data.

×：Allowing cookies to remain persistent in memory

This is incorrect because virtual storage is not associated with cookies. Virtual storage uses hard drive space to extend RAM memory space. Cookies are small text files used primarily by web browsers. Cookies can contain credentials for web sites, site preferences, and shopping history. Cookies are also commonly used to maintain web server-based sessions.

×：Side-channel attacks are possible.

Side-channel attacks are incorrect because they are physical attacks. This type of attack gathers information about how a mechanism (e.g., smart card or encryption processor) works from abandoned radiation, time spent processing, power consumed to perform a task, etc. Using the information, reverse engineer the mechanism to reveal how it performs its security task. This is not related to virtual storage.

×：Two processes can perform a denial of service attack.

The biggest threat within a system where resources are shared between processes is that one process can adversely affect the resources of another process, since the operating system requires memory to be shared among all resources. This is especially true in the case of memory. It is possible for two processes to work together to perform a denial of service attack, but this is only one of the attacks that can be performed with or without the use of virtual storage.

〇：Zero Knowledge Proof

Zero Knowledge Proof means that someone can tell you something without telling you more information than you need to know. In cryptography, it means proving that you have a certain key without sharing that key or showing it to anyone. Zero knowledge proof (usually mathematical) is an interactive way for one party to prove to another that something is true without revealing anything sensitive.

×：Key Clustering

Key clustering is the phenomenon of encrypting the same plaintext with different keys, but with the same ciphertext.

×：Avoiding Birthday Attacks

An attacker can attempt to force a collision, called a birthday attack. This attack is based on the mathematical birthday paradox present in standard statistics. This is a cryptographic attack that uses probability theory to exploit the mathematics behind the birthday problem.

×：Provides data confidentiality

Provided via encryption when data is encrypted with a key, which is incorrect.

〇：Conflict condition

A race condition is present when a process performs a task on a shared resource and the sequence could be in the wrong order. 2 or more processes can have a race condition if they use a shared resource, like data in a variable. It is important that processes perform their functions in the correct sequence.

×：Backdoors

Backdoors are incorrect because they are “listening” services on certain ports. Backdoors are implemented by attackers to allow easy access to the system without authenticating as a normal system user.

×：Maintenance Hooks

Maintenance hooks are specific software codes that allow easy and unauthorized access to sensitive parts of a software product. Software programmers use maintenance hooks to allow them to get quick access to the code so that they can make fixes in immediate, but this is dangerous.

×：Data validation errors

Data validation errors are wrong because an attacker cannot operate on the process execution sequence.

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：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：* (star) Integrity Property

The Biba model defines a model with completeness as having two axioms. The * (star) Integrity Property is that the subordinate’s document is to be seen and there is no Read Down. The * (star) Integrity Property is that there is no Write Up, that is, no rewriting of the supervisor’s document. If the Simple Integrity Axiom is not followed, the subordinate’s document will be seen and may absorb unclassified and incorrect information at a lower level. If the * (star) Integrity Property is not followed, a supervisor’s document will be rewritten, which will release incorrect information to the supervisor who sees it. Therefore, both are integrity conditions.

×：Simple Integrity Property

The Simple Integrity Property is a constraint on Read Down.

×：Strong Tranquillity Axiom

The Strong Tranquillity Axiom is the constraint not to change permissions while the system is running.

×：Weak Tranquillity Axiom

Weak Tranquillity Axiom means do not change privileges until the attribute is inconsistent.

〇：Zachman Framework

The Zachman Framework is an enterprise architecture that determines the what, how, where, who, when, and why for each mandate. Enterprise architecture is to create a management structure to achieve business goals. We create an organization to achieve business goals, and basically, the larger the business goals, the larger the organization. If the structure of the organization is not in place, the organization will not run efficiently, as there may be residual work that needs to be done, or there may be friction between jobs due to authority that is covered by others. Therefore, it is necessary to clarify the scope of each job authority in order to put the organization in order. The job authority here is different from the perspectives of human resources or sales. It is easier to think of them as hierarchically separated to achieve business goals. Clarify the scope in Executive, Business Management, Architecture, Engineers, Subcontractors, and Stakeholders, respectively. Therefore, the correct answer is the Zachman Framework.

×：SABSA

SABSA (Sherwood Applied Business Security Architecture) is a framework to ensure that security measures are working properly in achieving business goals. Unlike the Zachman Framework, the tasks to be organized are hierarchical elements. Business Requirements > Conceptual Architecture > Logical Service Architecture > Physical Infrastructure Architecture > Technology and Products, each with a 5W1H practice.

×：Five-W method

There is no such term. If there is, it is a term coined to make it easier to interpret.

×：Biba Model

The Biba model is a security model that indicates that data cannot be changed without permission.

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：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.

〇：Crime Prevention by Environmental Design (CPTED)

Crime Prevention by Environmental Design (CPTED) is a method by which crime can be reduced through proper design of the physical environment. It provides guidance on appropriate facility construction and environmental elements and crime prevention. It is used to guide the physical environment to behavioral effects that reduce crime.

×：Multi-layered defense model  

The multi-layered defense model is incorrect because it is a hierarchical architecture of physical, logical, and administrative security controls. The concept is that if one layer fails, the asset is protected by other layers. Layers should be moved from the perimeter toward the asset and implemented.

×：Hiding by Ambiguity

Concealment by ambiguity is a technique of concealment secured by concealment of information and is incorrect. Basically, it is better not to consider something to be a true secret if it is logically reachable, even if it is not public.

×：Access Control

Access control is incorrect because it is guidance by the placement of doors, fences, lighting, and landscaping as people enter. It is an abstract concept and would not fit into a concrete definition that combines sociology.

Cryptographic algorithms refer to the calculations to be encrypted, and even if the cryptographic algorithms were publicly available, it would take an enormous amount of effort to decipher them. cryptographic algorithms that provide modern cryptography, such as AES, are publicly available. On the other hand, in-house development is not recommended because, although it has the security of concealment, it requires a great deal of resources to be allocated.

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.

〇：Execution Domain Switching

Execution domain switching occurs when the CPU needs to move between executing instructions for a more trusted process versus a less trusted process. Trusted Computing Base (TCB) allows processes to switch domains in a secure manner to access different levels of information based on sensitivity. Execution domain switching occurs when a process needs to invoke a process in a higher protection ring. The CPU executes the user-mode instruction back into privileged mode.

At first glance, this is a geeky problem that does not make sense. But don’t give up. Since there is no such thing as skipping, you can only get a right or wrong answer when the question is posed, so it is preferable to answer the question with some degree of prediction.

From this point on, let’s consider how to answer the questions. If you look at the question text and read it to the point where it reads, “You moved from one area to the other, and that was a security breach?” If you can read to that point, then you have two choices: deny or “stop the process,” or change or “switch the domain of execution. Next, the question text reads “if you need to access it,” which is asking how to accomplish this objective, not whether or not you should.

×：Execution of I/O operations

This is incorrect because input/output (I/O) operations are not initiated to ensure security when a process in one domain needs to access another domain in order to retrieve sensitive information. I/O operations are performed when input devices (such as a mouse or keyboard) and output devices (such as a monitor or printer, etc.) interact with an application or applications.

×：Stopping a Process

A process deactivation is one that occurs when a process instruction is fully executed by the CPU or when another process with a higher priority calls the CPU, which is incorrect. When a process is deactivated, new information about the new requesting process must be written to a register in the CPU. The TCB component must ensure that this is done, since the data replaced in the registers may be confidential.

×：Mapping from virtual memory to real memory

Incorrect because memory mapping occurs when a process needs its instructions and data processed by the CPU. The memory manager maps logical addresses to physical addresses so that the CPU knows where to place the data. This is the responsibility of the operating system’s memory manager.

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：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.