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：Operating system patching is easier.

This is an incorrect choice question. Virtualization does not simplify operating system patching. In fact, it complicates it by adding at least one additional operating system. Each operating system differs from the typical version configuration, adding to the complexity of patching. The server’s own operating system runs as a guest within the host environment. In addition to patching and maintaining the traditional server operating system, the virtualization software itself must be patched and maintained.

For this question, we do not require an understanding of all the technical systems of virtualization. What is required here is a selection of answers based on a process of elimination.

×：I can build a secure computing platform.

Building a secure computing platform may not be a feature of virtualization per se. However, can we build a secure environment? This is not a false choice because it cannot be ruled out.

×：It can provide fault and error containment.

Virtualization can be host independent. In terms of containment, it can be interpreted as being able to provide fault and error containment through independence from physical servers. Therefore, it cannot be denied and is therefore not an incorrect choice.

×：It can provide powerful debugging capabilities.

Virtualization can reproduce a unique environment, not just put up a clean virtual host. Therefore, it is undeniable and therefore out of the wrong choice.

〇：The client generates a session key and encrypts it with a public key.

Transport Layer Security (TLS) uses public key cryptography to provide data encryption, server authentication, message integrity, and optionally client authentication. When a client accesses a cryptographically protected page, the web server initiates TLS and begins the process of securing subsequent communications. The server performs a three-handshake to establish a secure session. After that, client authentication with a digital certificate, as the case may be, comes in. The client then generates a session key, encrypts it with the server’s public key, and shares it. This session key is used as the symmetric key for encrypting the data to be transmitted thereafter. Thus, the correct answer is: “The client generates a session key and encrypts it with the public key.” will be

×：The server generates the session key and encrypts it with the public key.

The server does not encrypt with the public key.

×：The server generates a session key and encrypts it with the private key.

Even if encryption is performed from the server side, it can be decrypted with the public key, so it is not structurally possible.

×：The client generates a session key and encrypts it with its private key.

The client side does not have the private key.

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.

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：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：OCSP is a protocol developed specifically to check CRLs during the certificate validation process.

A Certificate Authority (CA) is responsible for creating certificates, maintaining and distributing them, and revoking them when necessary. Revocation is handled by the CA and the revoked certificate information is stored in a Certificate Revocation List (CRL). This is a list of all revoked certificates. This list is maintained and updated periodically. A certificate is revoked if the key owner’s private key has been compromised, if the CA has been compromised, or if the certificate is incorrect. If a certificate is revoked for any reason, the CRL is a mechanism for others to inform you of this information. The Online Certificate Status Protocol (OCSP) uses this CRL; when using CRLs, the user’s browser must examine the CRL value to the client to see if the accreditation has been revoked or the CA is constantly checking to make sure they have an updated CRL. If OCSP is implemented, it will do this automatically in the background. It performs real-time verification of the certificate and reports back to the user whether the certificate is valid, invalid, or unknown.

×：CRL was developed as a more efficient approach to OCSP.

CRLs are often incorrect because they are a cumbersome approach; OCSP is used to deal with this tediousness; OCSP does this work in the background when using CRLs; OCSP checks the CRL to see if the certificate has been revoked by Checks.

×：OCSP is a protocol for submitting revoked certificates to CRLs.

OCSP is incorrect because it does not submit revoked certificates to the CRL; the CA is responsible for certificate creation, distribution, and maintenance.

×：CRL provides real-time validation of certificates and reports to OCSP.

Incorrect because CRL does not provide real-time validation of certificates to OCSP.

〇：The most common method used is to change the most significant bit.

Steganography is a method of hiding data in other media types. One of the most common ways to embed messages in some types of media is using the least significant bit (LSB). This is because many types of files are modified and this is where sensitive data can be made visible and hidden without modifying the file. the LSB approach has been successful in hiding information within the graphics of high-resolution or sound-heavy audio files (high bit rate).

×：Hiding by abstraction.

Steganography is incorrect because it is concealment by abstraction. Security by obscurity means that someone uses secrecy as a way to protect an asset, rather than actually using the measure to secure something.

×：Just as encryption does, steganography is not a front for the existence of the sensitive data itself.

It is true that steganography does not draw attention to itself as does encryption. In other words, it is concealment by abstraction.

×：Media files are ideal for steganographic transmissions that are large in size.

This is incorrect because it is true that larger media files are ideal for steganographic transmissions because everyone needs to privately use multiple bits to manipulate with low likelihood of noticing.

〇：A virtual firewall in bridge mode allows the firewall to monitor individual traffic links, while a firewall integrated into the hypervisor can monitor all activity taking place within the host system.

Virtual firewalls can be bridge-mode products that monitor individual communication links between virtual machines. They can also be integrated within a hypervisor in a virtual environment. The hypervisor is the software component that manages the virtual machines and monitors the execution of guest system software. When a firewall is embedded within the hypervisor, it can monitor all activities that occur within the host system.

×：A virtual firewall in bridge mode allows the firewall to monitor individual network links, while a firewall integrated into the hypervisor can monitor all activities taking place within the guest system.

A virtual firewall in bridge mode is incorrect because the firewall can monitor individual traffic links between hosts and not network links. Hypervisor integration allows the firewall to monitor all activities taking place within the guest system rather than the host system.

×：A virtual firewall in bridge mode allows the firewall to monitor individual traffic links, while a firewall integrated into the hypervisor can monitor all activities taking place within the guest system.

A virtual firewall in bridge mode is wrong because the firewall can monitor individual traffic links, and the hypervisor integration allows the firewall to monitor all activity taking place within the host system, but not the guest system. The hypervisor is the software component that manages the virtual machines and monitors the execution of the guest system software. A firewall, when embedded within the hypervisor, can monitor all activities taking place within the system.

×：A virtual firewall in bridge mode allows the firewall to monitor individual guest systems, while a firewall integrated into the hypervisor can monitor all activities taking place within the network system.

A virtual firewall in bridge mode allows the firewall to monitor individual traffic between guest systems, and a hypervisor integrated allows the firewall to monitor all activity taking place within the host system, not the network system, so Wrong.

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：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.

〇：Encryption and decryption are more efficient.

Elliptic curves are rich mathematical structures that have shown usefulness in many different types of applications. Elliptic curve cryptography (ECC) differs from other asymmetric algorithms because of its efficiency; ECC is efficient because it is computationally less expensive than other asymmetric algorithms. In most cases, the longer the key, the more bloated the computation to secure it, but ECC can provide the same level of protection with a shorter key size than RSA requires.

×：Provides digital signatures, secure key distribution, and encryption.

ECC is wrong because it is not the only asymmetric algorithm that provides digital signatures, secure key distribution, and encryption provided by other asymmetric algorithms such as RSA.

×：Calculated in finite discrete logarithms.

Wrong because Diffie-Hellman and El-Gamal compute with finite discrete logarithms.

×：Uses a large percentage of resources to perform the encryption.

Incorrect because ECC when compared to other asymmetric algorithms uses much less resources. Some devices, such as wireless devices and cell phones, have limited processing power, storage, power, and bandwidth. Resource utilization efficiency is very important for the encryption methods used in this type.

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.

A key escrow system is one in which a third-party organization holds a copy of the public/private key pair. If the private key is stolen, all ciphers can be decrypted. Conversely, if it is lost, all ciphers cannot be decrypted. Therefore, you want to have a copy. However, if you have it yourself, it may be stolen if a break-in occurs, so you leave it with a third-party organization.

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：Well-Formed Transaction

In the Clark-Wilson model, subjects cannot access objects without going through some type of application or program that controls how this access is done. The subject (usually the user) can access the required object based on access rules within the application software, defined as “Well-Formed Transaction,” in conjunction with the application.

×：Childwall model

This is incorrect because it is another name for the Brewer Nash model created to provide access control that can be dynamically modified according to the user’s previous behavior. It is shaped by access attempts and conflicts of interest and does not allow information to flow between subjects and objects. In this model, a subject can only write to an object if the subject cannot read another object in a different data set.

×：Access tuples

The Clark-Wilson model is incorrect because it uses access triples instead of access tuples. The access triple is the subject program object. This ensures that the subject can only access the object through the authorized program.

×：Write Up and Write Down

The Clark-Wilson model is incorrect because there is no Write Up and Write Down. These rules relate to the Bell-LaPadula and Biba models. The Bell-LaPadula model contains a simple security rule that has not been read and a star property rule that has not been written down. The Biba model contains an unread simple completeness axiom and an unwritten star completeness axiom.

〇：The expiration date should be set short.

Key management is critical for proper protection. Part of key management is to determine the key’s period of validity, which would be determined by the sensitivity of the data being protected. For sensitive data, periodic key changes are required and the key’s expiration date will be shortened. On the other hand, for less secure data, a key with a longer expiration date is not a problem.

×：Keys should be deposited in case of backup or emergency.

This is incorrect because it is true that keys must be deposited in the event of a backup or emergency situation. Keys are at risk of being lost, destroyed or damaged. Backup copies must be available and readily accessible when needed.

×：Keys must not be made public.

Of course. It is a key.

×：Keys should be stored and transmitted by secure means.

Wrong, since it is true that keys should be stored and transmitted by secure means. Keys are stored before and after distribution. If keys are distributed to users, they must be stored in a secure location in the file system and used in a controlled manner.

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：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.