Ch5 CyberSecurity (Test and Practice)

I don't have unlimited learn and quizzes so I paste here

What is an Operating System (OS)?

A software that manages and handles hardware and software resources of a computing device.

What are the core functions of an Operating System?

Process management, memory management, and file management.

Why is the Operating System a valuable target for attackers?

Because it controls major resources such as memory, files, processes, hardware devices, and user access.

What types of malware can compromise an Operating System?

Viruses, Trojan horses, and other malicious programs.

How does the Operating System protect against unauthorized access?

By identifying and authenticating users and controlling access to files and other objects.

What is the role of security software in relation to malware?

To detect malware by examining patterns or behavior and to prevent it from entering memory or storage.

What is the importance of the boot process in OS security?

Security mechanisms need to start before potentially dangerous objects are allowed to execute.

What happens if malware executes before security software during the boot process?

The malware may gain control over the system, hide itself, and disable security measures.

What is the function of the Trusted Computing Base (TCB)?

To provide a secure environment for the operating system and its processes.

What is meant by 'object reuse' in the context of OS security?

Ensuring that data from previously used objects is not accessible to unauthorized users.

What is memory protection in Operating Systems?

A mechanism that prevents one program from reading or modifying another program's memory.

What is the purpose of interprocess communication in an OS?

To allow different processes to exchange information and coordinate their actions.

How does the OS ensure fair service to all users?

By using scheduling and hardware clocks to allocate resources fairly.

What is user authentication in the context of an Operating System?

The process of identifying users and confirming their identity, typically using a username and password.

What are some examples of devices that require an Operating System?

Home thermostats, pacemakers, automobiles, airplanes, smartphones, tablets, firewalls, and web servers.

What is the role of the OS in managing hardware resources?

To control how hardware is shared among users and applications.

What is the significance of modularity in secure OS design?

It enhances security by allowing components to be updated or replaced independently.

What is a rootkit?

Malware that compromises the operating system itself, often providing unauthorized access.

What is the purpose of encryption in OS security?

To protect critical operating system data from unauthorized access or modification.

What is the reference monitor in OS security?

A concept that enforces access control policies and ensures that all access to objects is authorized.

What does the OS do to prevent unauthorized programs from overwriting memory?

It implements memory protection mechanisms to isolate processes.

What is the function of access control information in an OS?

To determine which users or processes have permission to access specific resources.

How does the OS manage communication between programs?

By controlling access to shared resources and coordinating their interactions.

What is the importance of layering in secure OS design?

It allows for separation of concerns, making the system more manageable and secure.

What are some common operating systems?

Linux, Unix, Windows, Android, macOS, and iOS.

What is the role of the OS in resource sharing?

To allow users to share files, memory, devices, and data in a controlled manner.

What is the significance of hardware controls in OS security?

They provide additional layers of protection for critical data and resources.

What permissions can an operating system control?

Read, Write, Execute

What hardware features support memory protection?

Paging and Segmentation

What does the OS protect?

User files, system files, and input/output devices

What is an example of a permission a user may have?

A user may have Read permission but not Write permission.

What structures does the OS use for access control?

Access control tables or similar structures.

What are kernel functions in an operating system?

Basic OS security and resource management functions.

What is the core part of the operating system called?

The kernel

What are examples of protected objects in an OS?

Memory, disks, printers, tape drives, shared programs, networks, and shared data.

What does granularity of access control refer to?

How small or large the protected unit is.

What is the advantage of smaller granularity in access control?

More precise control.

What is the role of the security kernel?

To enforce security by checking permissions and controlling access.

What is a device driver?

A small software program that allows the OS to communicate with hardware devices.

What is the first step in the operating system boot process?

Basic I/O to gain access to the boot device.

What does the bootstrap loader do?

Loads the next parts of the operating system.

What is the purpose of the kernel in the boot process?

To initialize important low-level functions.

Why is the loading order of OS components important?

Security components must be available early enough to protect everything loaded afterward.

What are common access control techniques used by an OS?

Access Control Lists (ACLs), Privilege Lists, and Capabilities.

What does an Access Control List (ACL) do?

Shows which users can access a resource and what they can do.

What is a privilege list in access control?

Defines special permissions or privileges given to a user or process.

What is a capability in access control?

A special permission or token that allows access to a particular resource.

What must the OS do to protect itself?

Defend against malicious user programs, faulty drivers, and unsafe add-ons.

What is the significance of the OS having higher privileges?

It allows the OS direct hardware access and control over other programs.

What is the final step in the operating system boot process?

Loading the graphical interface and user services.

What is the purpose of the security kernel?

To enforce security by checking permissions and controlling access to important resources.

What is an example of a security-sensitive activity in password authentication?

Changing the stored password table.

What is the role of modules in modern operating systems?

To provide various functionalities like device drivers, file systems, and user interfaces.

What is a potential risk associated with system modules?

A vulnerable module may affect the entire operating system.

What does an audit log record?

Who accessed something, what they accessed, when, and what action they performed.

What is the main purpose of auditing?

To help investigate incidents by answering what happened, who did it, what data was affected, and when it happened.

What is virtualization?

Giving a user the appearance of having certain resources, even though the real resources are different underneath.

What is a virtual machine (VM)?

A VM behaves like a separate computer, capable of running different operating systems, applications, and security environments.

What is a hypervisor?

A hypervisor, or virtual machine monitor, manages virtual machines, receives resource requests, and redirects them to the correct real resources.

What is a sandbox?

A restricted environment where a program can run without having full access to the system, limiting potential damage from untrusted code.

What is a honeypot?

A fake or controlled system designed to attract attackers, allowing administrators to learn about their methods and intentions.

What is physical separation in security?

Using separate physical resources, such as different computers or printers, to keep users' resources distinct.

What is temporal separation?

Different users or processes use the same resource at different times.

What is logical separation?

The OS makes each process behave as though other processes do not exist, preventing access to each other's memory.

What is cryptographic separation?

Data is protected using encryption, making it unreadable without the proper key.

What does 'no protection' mean in terms of access levels?

Everyone can access everything without any special protection.

What is isolation in security?

Processes are completely separated, each having its own memory, files, and resources.

What does 'share but limit access' mean?

Different users can receive different permissions, such as read, write, or no access.

What is a fence in memory protection?

A basic method to stop a user program from accessing or damaging the operating system's memory.

What is a fence register?

A hardware register that stores the address where the operating system's memory ends, denying access to protected memory.

What are base and bounds registers?

Base register defines the starting address, and bounds register defines the ending limit for a process's memory access.

What is a context switch?

The process of changing from one process to another, which includes changing the base and bounds values.

What is tagged architecture?

Memory locations have extra information indicating what operations are permitted, providing finer protection.

What is virtual memory?

Allows programs to use logical addresses instead of knowing the true physical memory locations, enabling data movement and protection.

What is segmentation in memory management?

Divides a program into logical pieces, such as code, data, and stack segments, with each segment having its own permissions.

What is paging?

Divides memory into equal-sized pieces called pages, which can be stored in non-contiguous physical memory.

What is the problem with segmentation?

A program could try to access an offset outside the valid segment size, requiring the OS to check the offset's validity.

What are program pieces in an operating system called?

Pages

What are physical memory pieces referred to as?

Page frames

What components are combined in a system that uses both paging and segmentation?

Logical segments and fixed-size pages

What is the purpose of a page table in an operating system?

To translate a paging address into a real memory location

What is a key principle of secure OS design?

Simplicity of Design

What does layered design in operating systems help achieve?

Organizes the system and places sensitive functions deeper inside

What is the main function of a kernel in an operating system?

To control how the computer's hardware and programs work together

What is meant by 'modular' in good OS design principles?

Dividing the OS into smaller components

What does encapsulation in layered design refer to?

Hiding details of lower layers from higher layers

How does layering help limit damage in an operating system?

Problems in one layer are likely to stay contained within that layer

What is the significance of a reference monitor in OS security?

It enforces access controls and monitors interactions between subjects and objects

What are some examples of components that may complicate OS security?

Legacy code, device drivers, system libraries, third-party modules

What does the term 'brittle software' refer to?

Software that becomes difficult to understand, modify, test, or maintain

What is the main security idea in OS design?

Security should be included from the beginning of the design

What are the two main security benefits of layered design?

Critical parts receive more attention and problems can be contained

What is the role of interprocess communication (IPC) in an operating system?

It helps different running programs communicate with each other

What does the kernel do during interrupt handling?

Helps the computer respond to immediate attention needs

Why is complexity a security risk in operating systems?

More components create more possible entry points for attackers

What does 'loose coupling' mean in the context of OS design?

Components should depend as little as possible on each other

What is the purpose of message passing in an operating system?

Allows programs to send and receive messages or information

What is a critical aspect of secure design principles?

Clear design philosophy

What does logical separation in layered systems ensure?

Lower trusted layers control what higher layers are allowed to access

What is the main challenge in securing modern operating systems?

They may contain millions of lines of code, making it hard to ensure correctness