CISSP Domain 3 Flashcards
What are technique of ensuring CIA for processes?
1.Confinement: Process to be assigned only required resources (memory, run time)
2. Bound: Process is authorised to interactions user, Kernel
3. Isolation : Enforcement of bound and implementation of confinement
What is trust and Assurance?
Trust: Presence of security mechanism
Assurance: Degree of confidence in satisfaction of security needs
What is security model?
Map abstract statements into security policy for designers
What is TCB and it’s components?
Enforcement of security policy through:
- Security perimeter: Seperate trusted to in untrusted
- Reference monitor: Restrict the access it’s a theoretical concepts
- Security kernel: Implements the above RM
What is State machine model?
Takes snapshot of a system at given time
It should always be in “secure state”
When the state changes it’s called transition state and it should happen in secure transition state
What is information flow model ?
Multilevel security
Dictates information flow from subject to object to prevent unauthorised, restricted, insecure often between different security level
What are elements of Evaluation criteria?
Protection profile ( and Security Target ()
Non Interference
Actions of subject at a higher level should not take advantage of the lower level
Take grant model
Access rights can be passed on from an object to a different object
Access control matrix
Capability list and access control matrix
Bella padula
Protect confidentiality
simple security property ( no read up) and star security property (no write down)
Discretionary security property
Biba model
Integrity
No read down ( simple integrity rule)
No write up ( star integrity rule)
Clark Wilson model
Provide integrity
Access triplet ( subject, program and object)
Subjects cannot access objects directly but only through TP
CDI - constrained data item to protect integrity using security model
UDI - not restricted
Transformation Procedure - Will use TP for subject to access object
Brewer and nash model
Provides confidentiality
Chinese wall model or to avoid conflict of interest
Goguen - Meseguer model
Integrity
Foundation of non Interference model
Sutherland model
Prevention of interference+ integrity
Graham Denning model
Creation and deletion of both subjects and objects
Harrison -Ruzo -Ulman model
Assignment of object access rights and resilience of assigned rights
Secure design principles
Secure default
Fail securely: physical - digital
Fail open( people, availability)
Fail safe ( people, CI)
Fail closed and secure( assets, CI)
KISS
Zero trust : Microsegmentation, assume there is data breach, trust but verify,
privacy by design- (proactive, default setting, positive sum, data protection, visibility and transparency, user centric)
, trust but verify - now zero trust)
Shared Responsibility
Organization do not operate in isolation in an interconnected World you can have internal and external suppliers
Process and execution types
Brain of computer
- Ready : to be executed after fetching info from memory
- Running: Execution
- Waiting: Has 2 but need to fetch other data from memory in order to complete execution
- Supervisory
- Stopped
Problem state based on low prevlige access
CPU and processing types
Brain of computer
1. Multitasking: Multiple tasks a single core
2. Multi processing: Multiple process and multiple thread executed by processor
3. Multicore : Many core cpu
4. Multi threading: Many thread executed for a single process
5. Multi programming: similar to multitasking
Fetch execute decode
Protection mechanism of OS
Ring 0 kernel
Ring 1 os components
Ring 2 drivers and protocol
Ring 3 i/o devices
What is goal of memory protection and and how can it be achieved (2 methods)?
A computing device is likely running multiple applications and services simultaneously, each occupying a segment of memory. The goal of memory protection is to prevent one application or service from impacting another. There are two primary memory protection methods:
Process isolation: OS provides separate memory spaces for each processes instructions and data, and prevents one process from impacting another
Hardware segmentation: forces separation via physical hardward controls rather than logical processes; in this type of segmentation, the operating system maps processes to dedicated memory locations