Domain 3: Security Architecture and Engineering 13% Flashcards
DAC (Discretionary Access Control)
gives the subjects full control of objects they have created or been given access to.
MAC (Mandatory Access Control)
is system-enforced access control based on a subject’s clearance and an object’s labels.
RBAC (Role Based Access Control)
is where access to objects is granted based on the role of the subject.
ABAC (Attribute Based Access Control)
is where access to objects is granted based on subjects, objects AND environmental conditions.
RUBAC (Rule Based Access Control)
is access that’s granted based on IF/THEN statements.
Bell-LaPadula: Confidentiality (MAC)
Simple Security Property “No Read UP”
Security Property “No Write DOWN”
StrongProperty “No Read or Write UP and DOWN”
BIBA: Integrity (MAC)
Simple Integrity Axiom “No Read DOWN”
*Integrity Axiom “No Write UP”
Invocation Property “No Read or Write UP”
Lattice Based Access Control (LBAC)(MAC)
e.g. “Top Secret” crypto. chemical
Graham-Denning Model
uses Objects, Subjects, and Rules. The 8 rules that a specific subject can execute on an object are:
- Transfer Access
- Grant Access
- Delete Access
- Read Object
- Create Object
- Destroy Object
- Create Subject
- Destroy Subject.
HRU model (Harrison, Ruzzo, Ullman)
An OS level comp security model that deals with the integrity of access rights in the system. It is an extension of the Graham-Denning model. Considers Subjects to be Objects too. Uses 6 primitive operations: 1. Create object 2. Create subject 3. Destroy subject 4. Destroy object 5. Enter right into access matrix 6. Delete right from access matrix.
Clark-Wilson - Integrity
Separates end users from the backend data through ‘Well-formed transactions’ and ‘Separation of Duties’. The model uses Subject/Program/Object
Separation of duties
The certifier of a transaction and the implementer are different entities. The person making purchase orders should not be paying the invoices.
Well-formed transactions
is a series of operations that transition a system from one consistent state to another consistent state.
Brewer-Nash (Chinese Wall or Informaton Barriers)
Designed to provide controls that mitigate conflict of interest in commercial orgs, and is built upon an information flow model. No information can flow between the subjects and objects in a way that would create a conflict of interest.
Non-Interference Model
Ensures that any actions that take place at a higher security level do not affect, or interfere with, actions that take place at a lower level. The model is not concerned with data flow, but with what a subject knows about the state of the system. Any change by a higher level subject, will never be noticed by a lower level subject.
Take-Grant Protection Model
Uses rules that govern the interactions between subjects and objects. It uses permissions that subjects can grant to (or take from) other subjects. It has 4 rules:
1. Take rule allows a subject to take rights of another object. 2. Grant rule allows a subject to grant own rights to another object. 3. Create rule allows a subject to create new objects. 4. Remove rule allows a subject to remove rights it has over another object.
Access Control Matrix
Model describing the rights of every subject for every object in the system.
Zachman Framework (for Enterprise Architecture)
Provides 6 frameworks: What, How, Where, Who, When, Why
Mapping those frameworks to rules for: Planner, Owner, Designer, Builder, Programmer, User
Dedicated security mode
All users must have:
Signed NDA for ALL information on the system. Proper clearance for ALL information on the system. Formal access approval for ALL information on the system. A valid need to know for ALL information on the system. All users can access ALL data
System high security mode
All users must have: Signed NDA for ALL informaton on the system. Proper clearance for ALL information on the system. Formal access approval for ALL information on the system. A valid need to know for SOME information on the system. All users can access SOME data, based on their need to know.
Compartmented security mode
Signed NDA for ALL informaton on the system. Proper clearance for ALL information on the system. Formal access approval for SOME information on the system. A valid need to know for SOME information on the system. All users can access SOME data, based on their need to know and formal access approval.
Multilevel security mode - (Controlled Security Mode)
Signed NDA for ALL informaton on the system. Proper clearance for SOME information on the system. Formal access approval for SOME information on the system. A valid need to know for SOME information on the system. All users can access SOME data, based on their need to know, clearance and formal access approval.
The Orange Book
DOD Trusted Computer Systems Evaluations Criteria (TCSEC)
ITSEC (The European Info Tech Sec Evaluation Criteria)
Was the first successful int model. Contains a lot of references from The Orange Book, but both are retired now.
The International Common Criteria (ISO/IEC 15408)
Common Criteria evaluations are performed on computer security products and systems. To be of practical use, the evaluation must verify the target’s security features. This is done through the following: Target of Evaluation, Protection Profile, Security Target.
The International Common Criteria (ISO/IEC 15408) Evaluation Assurance Level (EAL)
How did the product score on the testing? EAL Level 1-7
EAL1: Functionally Tested
EAL2: Structurally Tested
EAL3: Methodically Tested and Checked
EAL4: Methodically Designed, Tested, and Reviewed.
EAL5: Semi-formally Designed and Tested
EAL6: Semi-formally Verifed Design and Tested
EAL7: Formally Verified Designed and Tested.
Layering
Separates hardware ans software functionality into layers.Layers can influeence layers next to themselves, but not past that.
Abstraction
Hiding unnecessary details fro teh user, it provides a seamless experience for the user, they don’t see the millions of background calculations.
Security Domains
A list of Objects a Subject is allowed to access, groups of Objects and Subjects with similar security requirements.
Kernel mode (Supervisor mode)
is where the kernel lives, allowing low-level unrestricted access to memory, CPU, disk, etc. Crashes are not recoverable
User mode (Problem mode)
has no direct access to hardware, it is directed through an API. Crashes are recoverable. This is most of what happens on a PC.
Open systems
use open standards, and can use standard components from multiple vendors.
Closed systems
use proprietary hardware and software. This is “security through obscurity.”
The Ring Model
4-ring model that seperates Users (Untrusted) from the Kernel (Trusted). Ring 3: User applications Ring 2: Device drivers Ring 1: Other OS Ring 0: Kernel Ring -1: Hypervisor mode
Northbridge (Mem controller Hub)
connected to it are: CPU, Video mem, RAM, and Southbridge
Southbridge
connected to it are: Mouse/keyboard, HD, USB, CD DVD
CPU
contains Arithmetic logic unit (ALU) for math functions and Control Unit (CU) traffic cop.
CPU 4 base functions
Fetch, Decode, Execute, Store
Pipelining- combining multiple steps into one process: can do many functions in same clock cycle.
CPU Interrupt
An interrrupt is a signal to the processor emitted by hardware or software indicating an event that needs immediate attention.
CPU Process
An executable program and its associated data loaded and running in memory. A heavy weight process (HWP) is also called a task. A parent process may spawn additional child processes called threads.
CPU Thread
Light Weight Process (LWP) Threads can share memory, resulting in lower overhead compared to heavy weight processes.
CPU Multithreading
is teh ability of a CPU or single core in a multi-core processor to execute multiple processes or threads concurrently, appropriately supported by the OS.
CPU multiprocessing
A comp using more than one CPU at a time for a task.
CPU Multitasking
tasks sharing a common resource ( 1 CPU)
CPU Multiprogramming
A computer running more than one program at a time (Word and Chrome at the same time).
CPU Memory protection
prevents one process from affecting the confid, integr, or availability of another.
CPU Process isolation
is a logical control that tries to prevent one process from Interfering with another.
CPU Hardware segmentation
takes that a step furhter by mapping processes to specific memory locations.
CPU Virtual Mem
provides virtual address mapping between applicaitons and hardware memory.
CPU Swapping
moves entire processes from primary mem (RAM) from/to secondary mem (HD)
CPU Paging
copies a block from primary memory (RAM) from/to secondary mem (HD)
BIOS
(Low level OS) BIOS runs a asic POST. Once the POST process is complet and successful, it locates the boot sector for the OS. The Kernel loads and exe, and teh OS boots. BIOS is stored on ROM most likely EEPROM
WORM Media (Write Once Read Many)
CD/DVDs can be WORM media (R)
TPM (Trusted Platform Module)
Is an int std for secure cryptoprocessor, which is dedicated microcont designed to secure hrdwr by integrating cryptographic keys into devices. Its is most commonly used to ensure boot integrity.
Data Execution Prevention (DEP)
is a security feature that can prevent damage to your computer from viruses and other security threats.
Address Space Layout Randomization (ASLR)
is a memory-protection proess for OS’; it guards against buffer-overflow attacks by randomizing the location where system executables are loaded into memory.
At the core of the OS is the Kernel
It interfaces between the OS (and applications) and the hardware.
Monolithic kernel
is one static executable and the kernel runs in supervisor mode.
Microkernels
are modular kernels
Reference monitor
is a core function fo the kernel; it handles all access between subjects and objects. It is always on and can’t be bypassed.
Windows NTFS
is a type of DAC (Discretionary Access Control)
Virtualization
we have many servers (clients) on the same hardware platform (host). Virtualization is software running under the OS and above the Hardware (Ring-1)
Hypervisor
control the access between the virtual guest/clients and the host hardware.
Type 1 hypervisor (Bare Metal)
is a part of a Virtualization OS that runs on top of the host hardware.
Type 2 hypervisor
runs on top of a regular OS like Win 10.
VM Escape
is when an attacker can jump from the host or a client to another client.
Cloud Computing
There is no ‘Cloud’ it is just another computer somewhere else.
IaaS (Infrastructure as a Service)
The vendor provides infrasturcutre up to the OS, the customer adds the OS and up.
SaaS (Software as a Service)
The vendor provides the OS and applications/programs. (O365, Gmail, Payroll)
PaaS (Platform as a Service)
The vendor provides pre-configured OSs, then the customer adds all the programs and applications.
Grid Computing
can make use of resources not currently in use from 100 or 100,000’s of computers to perform very complex tasks.
Peer to Peer (P2P0
Any system can be a client and/ or a server. Most commonly used on torrent networks.
Internet of Things (IoT)
Anything that connects to the Internet is some way (that didn’t before)
Emanations
often Electromagnetic Emanations. Info that can be disseminated from the electrical changes from a system or a wire.
Covert Channels
Creates the capability to transfer info. using channels not intended to do so.
Covert Timing Channels
Operations that affect the “real response time observed” by the receiver.
Covert Storage Channels
Hidden info through the modification of a stored object.
Steganography
hiding a message within another media
Digital Watermarks
encode data into a file
Virus
require some sort of huma interaction and are often transmitted by USB or other portable devices.
Polymorphic viruses
Change their signature to avoid the antivirus signature definitions
Multipart (Multipartite) Viruses
Spread across multiple vectors. They are often hard to get rid of because even if you clean the file infections, the virus may still be in the boot sector and vice-versa.
Worms
spread through self propagation.
Trojan
malicous code embedded in a program that is normal
Rootkits
replaces some of the OS/Kernel with a malicous payload.
Logic Bombs
Malicious code that executes at a certian time or event.
Packers
Programs to compress *.exe files, which can be used to hide malware in an executable, neutral tech.
Antivirus software
Signature based - looks for known malware signatures
Heuristic (Behavioral) based - looks for a abnormal behavior
Server (Service) Side Attack
Attack directly from an attacker to a target.
Client Side Attacks
The client initiates, then gets infected with malicious constent usually from web browsers or IM apps (You go to them)
Applets
small apps often embedded into other software (web browser)
Java
applets run in a sandbox environment - segmenting the Java from the OS (limiting some threats); OS agnostic
Active X
runs with certificates (not sandbox) - since Active x is a MS prod it interacts more with the OS (Win only)
SOA (Service-Oriented Architecture)
is a style of software design where services are provided to the other components by application components, through a communication protocol over a network.
Polyinstantiation (Alternative Facts)
Two (or more) instances of the same file depending on who accesses it.
Aggregation
is a collection of gathering of data together for the purpose of statistical analysis.
Inference
requires deducing from evidence and reasoning rather than from explicit statements
Data mining
is the computing process of discovering patterns in large data sets.
Data Analytics
is looking at what normal operations look like, then allowing us to more proactively identify abuse from insider threats or compromised accounts.
ICS (Industrial Control Sys)
is a general term for several types of control sys and associated inst used in indust prod technology
SCADA (Supervisory Control and Data Acquistion)
is a control sys arch that uses comp, network data comm and GUI for high-level process supervisory management.
DCS (Distributed Control Systems)
is a comp control sys for a process or plant in which autonomous controllers are distributed throughout the system, but there is central operator supervisory control.
PLC (Programmable Logic Controllers)
is an industrial digital computer which has been ruggedized and adapted for the control and manufacturing processes.
DNP3 (Distributed Network Protocol)
a set of comm protocols used between components in process automation systems. Comm between a master station and remote terminal units (RTU) or IEDs.