Domain 3 Flashcards
Shared Responsibility Model
On-Prem
(How Responsibility is delegated)
You 100%
- Apps
- Data
- Runtime
- Middleware
- OS
- Virtualization
- Servers
- Storage
- Networking
Shared Responsibility Model
IaaS
(How Responsibility is delegated)
You 50%
- Apps
- Data
- Runtime
- Middleware
- OS
Cloud Service Provider 50%
- Virtualization
- Servers
- Storage
- Networking
Shared Responsibility Model
PaaS
(How Responsibility is delegated)
You 25%
- Apps
- Data
Cloud Service Provider 75%
- Runtime
- Middleware
- OS
- Virtualization
- Servers
- Storage
- Networking
Shared Responsibility Model
SaaS
(How Responsibility is delegated)
Cloud Service Provider 100%
- Apps
- Data
- Runtime
- Middleware
- OS
- Virtualization
- Servers
- Storage
- Networking
Public Cloud
(Name the Pros)
Everything runs on CSP hardware
Scalable, Agile, pay-as-you-go, no maintenance, low skill
Private Cloud
(Name the Pros)
A cloud env in your own data center
legacy support, control, compliance
Hybrid Cloud
(Name the Pros)
Combines both Public / Private, allows you to run your apps in the right location
flexibility in legacy / compliance / scalability
Cloud Access Security Broker (CASB)
Security policy enforcement solution that may be install On-prem or in the cloud
Shadow IT Prevention
Post-Quantum Cryptography
Developing new cryptographic approaches developed by normal computers to be resilient to Quantum computers
How well do current encryption hold up to Quant?
Post-Quantum Cryptography
Symmetric Encryption
- Does better
-
Grovers Algorithm: Shows Quant computer halve key length
- 256 bit key is as strong as a 128 bit to a normal computer
Post-Quantum Cryptography
Asymmetric Encryption
- Does worse
-
Shor’s Algorithm: can easily break public key algos
- RSA & Elliptic Curve is vulnerable
- Lattice offers resilience
Post-Quantum Cryptography
Lattice Algorithms
Based on shortest vector problem and closest vector problem
- potential to replace all current endangered schemes
- Lattice based schemes make up most publications on post-quant crypto
TIP: If a ?’s ask ab a “asymmetric encryption” that is “quant resilient”, answer is Lattice
Cryptography
Code
Crypto system of symbols that operate on words or phrases and are sometimes secret but do NOT ensure confidentiality
Cryptography
Cypher
Always meant to hide true meaning
Types of Cyphers
Stream
Symmetric key, plaintext combined with cypher digit stream ( key stream ) . Each plaintext digit is encrypted one at a time with the corresponding digit on keystream to produce cipher text stream
Types of Cyphers
Block
encrypts plain text in blocks at a time, like 64- bits
Types of Cyphers
Substitution
replace each character with a different one. Ex ceasar cipher
Types of Cyphers
Transposition
Shuffle each digit
Initialization Vector (IV)
( Random Number ) a random string ( nonce ) that is XORed with message
used by ceasar, Vigenere, One time Pad
- main diff bt them is key length
- 1 char > word / sentence > one time pad
One Time Pad
Type of substitution cypher where key stream is at least as long as the message.
Success needs:
- generated randomly
- at least as long as message
- protected from disclosure
- Pad used once then deleted
Zero Knowledge Proof
specific info is exchanged but no real data transferred, only with digital signatures and certs
Prove knowledge of a fact without revealing the fact
Split knowledge
The privilege required to do operation is divided among multiple users
- no single person can comprimise security
Work Function (Work Factor)
Way to measure strength of crypto function by cost / time to decrypt message
Nonrepudiation
provide undeniable proof that sender actually authored it.
- prevents sender from denying it
DES Modes
Electronic Codebook Mode (ECB)
Least Secure, encrypts 64 bit blocks with the same key.
- if same block in plaintext, same ciphertext generated
DES Modes
Cipher Block Chaining (CBC)
Plaintext XORed with Cipher text immediately preceding
DES Modes
Cipher Feedback (CFB)
Streaming version of CBC, Works on data in real time, used memory buffers of same block size. When buffer fills, data is encrypted and transmitted. Uses chaining, so errors propagate.
DES Modes
Output Feedback (OFB)
Similar to CFB, XORs plaintext with seed value. No chaining so less propagated errors
DES Modes
Counter (CTR)
Uses incrementing counter rather than a seed
Key Clustering
Weakness where same ciphertext is generated from 2 different keys
Asymmetric Key Types
Hash Function Requirements
- Inputs of any length
- Fixed length outputs
- Relatively easy to compute hash for any input
- Provide 1 way functionality
- Collision Free
Asymmetric Key Types
Rainbow Tables
Pre-computed values to ID common passwords
Asymmetric Key Types
Salt
Random data added to hash input.
- salts reduce effectiveness of rainbow tables
Asymmetric Key Types
Digital Signature Standard (DSS)
Uses SHA-1, SHA-2, SHA-3, message digest functions.
Works in conjunction with 1 of 3:
1. Digital Signature Algorithm (DSA)
2. Rivest, Shamir, Alderman (RSA)
3. Elliptic Curve DSA (ECDSA)
Public Key Infrastructure (PKI)
Certificate Authorities (CA)
Body’s that generate Digital Certificates containing public keys of systems’ Users
- Users distribute certs to who they want to talk to
- Cert recipient verify a cert using CA’s public key
Securing Web Traffic
Email (Protocols)
- S/MIME
- Pretty Good Privacy (PGP)
Securing Web Traffic
Web (Protocols)
- HTTP over Transport Layer Security (TLS)
replacing SSL
Securing Web Traffic
Network
IPsec
Securing Web Traffic
IPsec
Architecture framework that supports secure communications over IP
- Establishes a secure channel in either transport mode or tunnel mode
- Can be used to establish direct comms between computers over VPN
- Uses 2 Protocols
- Authentication Header (AH)
- Encapsulating Security Payload (ESP)
Digital Rights Management (DRM)
Allow conent owners to enforce restriction on use of their content by others
- Common in entertainment industry
- Sometime protects sensitive info stored in docs
Top 3 Public Key Cryptosystems
RSA
Factoring product of prime numbers
Top 3 Public Key Cryptosystems
El Gamal
Modular arithmetic
Top 3 Public Key Cryptosystems
Elliptic Curve
Elliptic curve discrete logarithm problem and provides more security than the other 2
Digital Signature
Rely on public key crypto / hashing
MUST use SHA-2+ hashing
Currently approved:
- DSA
- RSA
- Elliptic Curve DSA
Security Model
Used to determine how security is implemented
- Formalize security Policy
- enforce CIA triad
- models lay out broad guidelines
- up to devs to decide how its functionally implemented
Top –> Down
- Security Policy
- Security Model
- Program Code
- OS
State Machine Model (SMM)
System is always secure, no matter what state it is in
- Based on FSM
- State - snapshot of a system
- if each state transition results in another secure state = SMM
Information Flow Model (IFM)
Based on SMM, focused on flow of information
- Biba = Flow from low to hight security level
- **Bell - LaPadula = prevent info from high to low
Non-Interference Model
How actions f high level affect system state of action at a low level
- ensures actions dont interfere with each other
Lattice Based Models
Interactions between
- objects - resources, computers, apps
- subjects - users, groups, orgs
Used to ID levels of security for obj / subj
3 Properties for Models
- Simple - Rules for read
-
Star - Rules for write
3, Invocation - Rules for calls to subjects
Security Models
Biba
Based on Integrity
No Read down, no write up
- Lattice Based
- Simple integrity = “no read down”
- Star integrity = “no write up
Security Models
Bell-LaPeluda
Based on Confidentiality
No read up, no write down
- SMM enforces Confidentiality
- Uses Mandatory Access Controls
- Simple security policy “no read up”
- Star property “no write down”
- Lattice Based
Security Models
Clark - Wilson
Integrity
Access Control Triple, uses security labels to access objects
Security Models
Goguen- Meseguer
Integrity
Non-interference
Security Models
Sutherland
Integrity
Prevent interference, info flow / SMM
Security Models
Brewer + Nash
Confidentiality
“Chinese Wall”
Prevents conflict of interest
Security Models
Take Grant
Confidentiality
uses “direct graph”
Supports 4 operations:
1. Take
2. Grant
3. Create
4. Revoke
Security Model: Clark - Wilson
Constrained Data Item (CDI)
data item who integrity is protected by the security model
Security Model: Clark - Wilson
Unconstrained Data Item (UDI)
data item that is NOT controlled by security model
Security Model: Clark - Wilson
Integrity Verification Procedure (IVP)
a procedure that scans data items and confirms their integrity
Security Model: Clark - Wilson
Transformation Procedure (TP)
Only process allowed to modify a CDI
Security Model: Clark - Wilson
Access Control Triplet
- Authenticated Principal (User / Subjects)
- Programs (TPs)
- Data Items (UDIs + CDIs) (objects)
Security Models
Graham - Denning Model
Protection rules where each object has an owner and controller
- focus on secure creation and deletion of both subject and object
- 8 primary protection rules:
- Securely create object
- Securely create subject
- Securely delete object
- Securely delete subject
- Securely provide the read access
- Securely provide the grant access
- Securely provide the delete access
- Securely provide the transfer access
Symmetric Cryptography Algorithms Table
Hash Algorithms Table
Asymmetric Cryptography Algorithms Table
Security Modes
Dedicated Mode
Security clearance that permits access to ALL info processed by system, approval for ALL info processed by system, and valid need-to-know for ALL info processed by system
Security Modes
Multilevel Mode
Can process info at different levels even when all system users do not have the required security clearance to access all info processed by the system
Security Modes
System High Mode
Each user must have valid security clearance, access approval for ALL info processed by system, and valid need-to-know for at least SOME info on the system. Offers most granular control over resources and users of thew modes
Security Modes
Compartmented Mode
Goes one step further than system high mode
Each user must have a valid security clearance access approval for ALL INFO processed by system, but requires valie need-to-know for ALL INFO they will have access to on the system
Trusted Computing Base
A combination of hardware, software and controls that work together to form a “trusted” base” to enforce your security policy.
- Is a subset of the complete information system.
- is the only portion that can be trusted to adhere to and enforce your security policy
- TCB must create secure channels ( trusted paths ) to communicate withthe rest of the system
- Protects subject from comprimise as a result of TCB interchange
Trusted Computing Base
Security Perimeter
An imaginary boundary that separates TCB from the rest of the system.
Trusted Computing Base
Reference Monitor
the logical part of the TCB that confirms whether a subject has the right to use a resource prior to granting access
Enforces access control
Trusted Computing Base
Security Kernel
The collection of the TCB components that implement the functionality of the reference monitor.
Implements access control
TCSEC, ITSEC, and CC
Common Criteria (CC, ISO-IEC 15408)
Enables and objective evaluation to validate that a particular product or system satisfies a defined set of security requirements
Has replaced TCSEC and ITSEC
TCSEC, ITSEC, and CC
Tusted Computer System Evaluation Criteria ( TCSEC )
A structured set of criteria for evaluating computer security within products and systems
TCSEC, ITSEC, and CC
Infomation Technology Security Evaluation Criteria (ITSEC)
Initial attempt to create a security eval criteria in Europe. Uses 2 scales to rate functionality and assurance
TCSEC, ITSEC, and CC
Common Criteria (ISO-IEC 15408)
Cycle
Assumptions & Security Policies
1. Description of Assets
2. ID of Threats
Safety Risk Analysis
3. Analysis & Rating of Threats
System & Environment Objectives
4. Determination of Security Objectives
5. Selection of Security Functional Requirements
6. Repeat
Two Flavors
1. community Protection Profile (cPP) = black box
2. Evaluation Assurance Level (EAL) = white box
TCSEC, ITSEC, and CC
Comparison of security eval standards Table
Video 3:05:28
Covert Channels
A method used to pass info over a path that is not normally used for comms.
- It may not be protected by the system’s normal security controls
Two Types
1. Covert Timing - based on time it takes to access components: paging rate, transaction time
2. Covert Storage - Out of band storage used to convey a message: ICMP protocol uses extra storage in Ping packet to relay info
Trusted Platform Module
A Chip that is on the motherboard of a device
- Multi-purpose, like storage and mnmgt of keys used for full disk encryption (FDE) solutions
- Provides OS with access to keys, but prevent drive removal and data access
Types of Access Control
Mandatory Access Control (MAC)
Enforces an access policy that is determined by the system, not the object owner.
- Relies on classification labels that are representative of security domains and realms
KEY POINT
- Every object and subject has one or more labels. These labels are predefined, and the system determines access based on assigned labels
- Refered to as lattice-based model
Types of Access Control
Discretionary Access Control
Permits the owner or creator of an object to control and define its accessibility, because the owner has full control by default
determined by owner
Types of Access Control
Non-discretionary Access Control
Enables the enforcement of system-wide restrictions that override object-specific access control.
System wide
Types of Access Control
Rule-based Access Control
Defines specific functions for access to requested objects. Commonly found in firewall systems
Applies global rules that apply to all subjects. (restrictions or filters)
Types of Access Control
Role-Based Access Control
Uses a well-defined collection of named job roles to endow each one with specific permissions, thereby seeking to ensure that users who occupy such roles can access what they need to get their jobs done.
MAC Model Classifications
Hierarchical Environment
Various classification labels are assigned ina ordered structure from low to medium to high security
MAC Model Classifications
Compartmentalized environment
Requires specific security clearances over compartments or domains instead of objects
MAC Model Classifications
Hybrid environment
Contains level with compartments that are isolated from the rest of the security domain.
- Combines hierarchical and compartmentalized environments so that security levels have submcompartments
Security Models, Design, and Capabilities
Certification
Technical Evaluation of each part of a computer system to assess is in agreement with security standards
Security Models, Design, and Capabilities
Accreditation
The process of formal acceptance of a certified config from a designated authority.
Security Models, Design, and Capabilities
Open System
Are designed using industry standards and are usually easy to integrate with other open systems
Security Models, Design, and Capabilities
Closed Systems
Are generally proprietary hardware and / or software.
- The specifications are
NOTnormally published and they are usually harder to integrate with other systems
Ensuring CIA Triad
Confinement
Restricts a process to reading from and writing to certain memory location
Ensuring CIA Triad
Bounds
The limits of memory a process cannot exceed when reading or writing
Ensuring CIA Triad
Isolation
The mode a process runs in when it is confined through the use of memory bounds
Factors of Authentication
Something you:
- Know (pin / password)
- Have (trusted device)
- Are (biometric)
Authentication (AuthN)
The process of proving that you are who you say you are
Identity control
Authorization (AuthZ)
The act of granting an authenticated part permission to do something
Access control
Multitasking
Simultaneous execution of more that one app on a computer and is managed byt the OS
Multithreading
Permits multiple concurrent tasks to be performed within a single process.
Multiprocessing
The use of more than one processor to increase computing power
Multiprogramming
Similar to multitasking, but takes place on mainframe systems and requires specific programming
Processor Operating Modes
User
Applications operate in a limited instruction set environment known as user mode
Processor Operating Modes
Privileged
Controlled operation are performed in privileged mode, also known as system mode, kernel mode, and supervisory mode.
Memory Types
Read-only Memory (ROM)
Read-only. Contents burned in at factory
Memory Types
RAM
Static RAM (SRAM) uses flip flops, dynamic RAM (DRAM) uses capacitors
Memory Types
PROM
Programmable chip similar to ROM, with several sub-types
Memory Types
EPROM
Erasing, Clearing (overwriting with unclassified data)
Two Types:
1. Ultraviolet EPROM (UVEPROM): Chip have a small window tha4t, when illuminated with a special UV light, erases contents
2. Electronically Erasable PROM (EEPROM) Uses electric voltages delivered to the pins of the chip to force erasure. *more flexible alternative to UVEPROM)
Memory Types
Flash Memory
Derivative concept from EEPROM. Nonvolatile can be electronically erased and rewritten
Security Issues With Storage
Primary Storage
same as memory
Security Issues With Storage
Secondary Storage
Consists of magnetic, flash, and optical media that mus be first read into primary memory before the CPU can use the data
Security Issues With Storage
Random Access Storage Devices
can be read at any pointSecurity Issues With Storage
Security Issues With Storage
Sequential Access Storage Devices
require scanning through all the data physically stored before the desired location
Security Issues With Storage
3 Main Issues
- Removable media can be used to steal data
- Access controls and encryption must be applied to protect data
- Data can remain on the media even after file deletion or media formatting
Security Risks of Input / Output Devices
- Subject to eavesdropping and tapping
- Used to smuggle data out of an org
- Used to create unauthorized / insecure points of entry to a orgs system and networks
Firmware
Software stored on a ROM chip, containing basic instructions needed to start a computer. Also used to provide operating instructions in peripheral devices such as printers
Vulnerabilities, Threats, & Countermeasures
Process Isolation
ensures that individual processes can access only their own data
Vulnerabilities, Threats, & Countermeasures
Layering
Creates different realms of security within a process and limits communication between them
Vulnerabilities, Threats, & Countermeasures
Abstraction
Creates **black-box* interfaces for programmers to use without requiring knowledge of an algorithms or device inner workings
Vulnerabilities, Threats, & Countermeasures
Data Hiding
Prevents information from being read from a different security level. Hardware segmentation enforces process isolation with physical controls.
The Role of Security Policy
To inform and guide the design, development, implementation, testing, and maintenance of some particular system
Hypervisor
Also known as Virtual Machine Monitor (VMM) is the component of virtualization that creates, manages, and operates the VMs
Two Types
1. Type I hypervisor: A native or bare-metal hypervisor. In this config, there is no host OS; instead the hypervisor installs directly onto the hardware where the host OS would normally reside
2. Type II hypervisor: A hosted hypervisor. in this config a standard regular OS is present on the hardware, and the hypervisor is then installed as another software application.
Security-aaS
A cloud provider concept in which security is provided to an org through or by an online entity
Smart Devices
Mobile devices that offer customization options, typically thru installing apps and may use on-device or in-the-cloud AI processing
Mobile Device / App Security
Mobile Device Security
The range of potential security options or features that may be available for a mobile device. security features include full device encryption, remote wiping, lockout, screen loicks, GPS, app control etc
Embedded Systems & Static Environments
Embedded System
Typically designed around a limited set of specific functions in relation to the larger product of which its a component
needs security management
Embedded Systems & Static Environments
Static Environment
applications, OSs, hardware sets, or networks that are configured for a specific need, capability, or function and then set to remain unaltered
needs security management
Privilege & Accountability
Principle of least privilege
Ensures that only a minimum number of processes are authorized to run in supervisory mode.
Privilege & Accountability
Separation of privilege
Increases the granularity of secure operations
Privilege & Accountability
Accountability
Ensures that an audit trail exists to trace operations back to their source
Common Flaws & Vulnerabilities
Buffer Overflow
Occurs when the programmer fails to check the size of input data prior to writing the data in a specific memory location.
Common Flaws & Vulnerabilities
(List 3 more)
- leaving back doors
- leaving privileged programs on a system after it is deployed.
- Time-of-check-to-time-of-use (TOCTTOU) attacks: any state change presents an opportunity for an attacker to compromise a system
Functional Order of Security Controls
- Deterrence - discourage any malicious actions
- Denial - Deny malicious action
- Detection - Detect and track activity
- Delay - Delay the progress
- Determine - the cause of the incident and figure out what is happening
- Decide - decide on the response to implement
If one fails move to next
Physical Security Controls
Administrative
Include policies and procedures like
- site management
- personnell controls
- awareness training
- emergency response
Physical Security Controls
Logical / Technical
Implemented through technology like
- access controls
- intrusion detection
- alarms
- CCTV
- monitoring
- HVAC
- power supplies
- Fire detection / suppression
Physical Security Controls
Physical
- Fencing
- Lighting
- Locks
- Construction materials
- Mantraps
- Dogs
- Guards
Physical Security Controls
Fence Types
3-4 Feet: deters casual trespasser
6-7 ft: to hard to climb easy
8 ft (w/barbed wire) - will deter intruders
Physical Security Controls
Temperature
Humidity: 40-60% ideal
Temps: for computers 60-75degF. Damage at 175degF. Manage storage devices damaged at 100F
Physical Security Controls
Electrical impacts - Blackout
Prolonged loss of power
Physical Security Controls
Electrical impacts - Brownout
Prolonged low voltage
Physical Security Controls
Electrical impacts - Fault
short loss of power
Physical Security Controls
Electrical impacts - Surge
Prolonged high voltage
Physical Security Controls
Electrical impacts - Spike
Temporary high voltage
Physical Security Controls
Electrical impacts - Sag
Temporary low voltage
Physical Security Controls
Lights
8 feet hight with 2 feet candle power
Physical Security Controls
Humidity + Static Electricity
Too much humidity can cause corrosion. Too litte causes static electricity even on non-static carpet, low humidity can generate 20,000-volt static discharge!
Fire / Suppression Agents
Class A (ASH)
Common combustibles such as wood, paper, etc. Shjould be extinguised with water or soda acid
Fire / Suppression Agents
Class B (BOIL)
Buring alcohol, oil, other petroleum products such as gasoline. Extinguished with gas or soda acid
Fire / Suppression Agents
Class C (CONDUCTIVE)
Electrical fires. Must be extinguished with non-conductive agaent like any type of gas
Fire / Suppression Agents
Class D (DILYTHIUM)
Burning metals. Extinguished by dry powder
Fire / Suppression Agents
Class K (KITCHEN)
Kitchen fires. Extinguished by wet chemicals
Fire / Suppression Agents
3 Categories of Fire Detection
- Smoke sensing
- Flame sensing
- Heat sensing
Voltage and Noise
Electromagnetic Interference - Common mode noise
Generated by the difference in power between the hot and ground wires of a power source.
Voltage and Noise
Electromagnetic Interference - Traverse mode noise
Generated by a difference in power in the hot and neutral wires of a power source
Voltage and Noise
Radio Frequency Interference (RFI)
The source of interference that is generated by electrical appliances, light sources, electrical cables and circuits etc
Damage from Fire and Fire Suppression - What do these things damage?
Smoke
Storage devices
Damage from Fire and Fire Suppression - What do these things damage?
Heat
Any electronic or computer component
Damage from Fire and Fire Suppression - What do these things damage?
Suppression mediums
Cause short circuits, initiate corrosion, or otherwise render equipment useless
Water Suppression Systems
Preaction Systems
Good for areas with people and computers
Use closed sprinkler heads and the pipe is charged with compressed air instead of water. The water is held in check by an electrically operated sprinkler valve and the compressed air
Water Suppression Systems
Wet Pipe Systems
Filled with water.
Water Suppression Systems
Dry pipe systems
have closed sprinkler heads. filled with compressed air. The water us held back by a valve that remains closed as long as sufficient air pressure remains in the pipes
used where water is likely to freeze
Water Suppression Systems
Deluge Systems
Similar to dry pipes, except the sprinkler heads are open and larger than dry pipe heads. The pipes empty at normal air pressure, the water is held back by a deluge valve
Gas Discharge Systems
More effective than water discharge systems but should not be used where people are because it removes oxygen from the air
Halon effective but bad for the environment (ozone-depleting), turns to toxic gas at 900F.
Lock Types
Electronic Combination Locks
(Cipher lock) Something you Know
Lock Types
Key Card Systems
Something you have
Lock Types
Biometric Systems
Something you are
Lock Types
Conventional Locks
Easily picked / bumped and keys easily duplicated
Lock Types
Pick and bump resistant Locks
Expensive, harder to pick, & Keys not easily duplicated
Site Selection
(Important considerations)
- Visibility
- Composition of the surrounding area,
- area accessibility
- effects of natural disasters
Facility Design
(Important considerations)
- Understanding level of security needed by your orgs and planning for it before construction begins
How to design / configure secure work areas
- should
NOTbe equal access to all locations - Valuable and confidential assets should be located in the center of protection
- Centralized server / computer rooms do not need to be human compatible
Threats to Physical Access Controls
Abuses
Propping open secured doors and bypassing locks or access controls
Threats to Physical Access Controls
Masquerading
Using someone elses ID badge to get in
Threats to Physical Access Controls
Piggybacking
Following someone through a secured door without swiping your badge
Security concerns of a wiring closet
- prevent physical unauthorized access
How to handle visitors in a secure facility
- escort assigned to visitor
- Tracking actions
Protections for evidence storage
- locked cabinets / safes
- dedicated / isolated storage facilities
- offline storage
- access restrictions / activity tracking
- hash management and encryption
Uninteruptable Power Supply (UPS)
Type of self charging battery that can be used to :
- supply consisten and clean power
- supply power in the event of a power failure
Access Control Models
Attribute Based Access Control
Uses rules that can include multiple attributes.
- Allows it to be more flexible than rule based model that applies rules to all subjects equally
- Often used by Software Defined Networks (SDNs)
