Modules 1 + 2 Term -> Def Flashcards
CIA Triad
A model for guiding security policies in an organization.
Confidentiality
Ensuring that data is only accessible to authorized individuals.
Integrity
Maintaining accuracy and consistency of data over its lifecycle.
Availability
Ensuring that authorized users have reliable access to data and services.
AAA
Authentication, Authorization, and Accounting framework.
Identification
Claiming an identity in a system.
Authentication
Proving identity using credentials.
Authorization
Granting access to resources based on identity.
Accounting
Tracking actions and accesses in a system.
3 States of Data
Three conditionsff under which data exists. : at rest, in transit, in use
In Transit
Data that is being transmitted across networks.
At Rest
Data stored in a persistent storage medium.
In Use
Data actively used by a process.
Non-Repudiation
Ensuring that a sender cannot deny having sent a message.
Gap Analysis
Comparison of security measures against requirements.
Vulnerability
A weakness in a system or process.
Threat
A vulnerability with a threat actor.
Risk
The probability and impact of a threat.
Data Sovereignty
Compliance with local data storage regulations. the country of the user about whom the data is stored governs that data.
Security Controls
Methods for managing security risks.
Categories of Security (STOMP)
Security control classifications.
Security is:
Technical
Operational
Managerial
Physical
Deterrent
Discouraging unauthorized actions.
Preventative
Preventing security incidents.
(eg lock on product case)
Detective
Detecting security breaches.
Corrective
Restoring system integrity after an attack.
Compensating
Back up for another security control or weakness. For example, password strength requirements and two factor authentication.
Directive
Enforces a rule or behavior, specifying how people should interact with a system
For example, policies, and disciplinary procedures
Physical Security Controls
Security measures in physical spaces.
Lighting
Enhancing security with visibility.
Fencing
Defining secure perimeters.
Cameras
Monitoring areas for unauthorized activity.
Bollards
Blocking unauthorized vehicular access.
Access Control Vestibule
Two door enclosure with an entry and exit.
Only one door can be opened at a time. Prevents 1) piggybacking, when you knowingly, let the person in using your credentials and
2) tailgating, which is when someone slips through the door after you unbeknownst to you.
Sensors & Alarms
Detecting motion and other activities.
DHKE
Diffie-Hellman Key Exchange, a method for securely exchanging cryptographic keys.
Publicly Agreed Numbers
• Alice and Bob agree on two public numbers:
• A large prime number (let’s call it P)
• A base/generator (let’s call it G)
These numbers don’t need to be secret and can be known to everyone, including an attacker listening in.
- Each Person Picks a Secret Number
• Alice picks a private number (a)
• Bob picks a private number (b)
• These are never shared with anyone, not even each other. - Compute and Exchange Public Values
Each person uses their private number to compute a public value:
• Alice calculates:
A = (G^a) mod P (She sends A to Bob)
• Bob calculates:
B = (G^b) mod P (He sends B to Alice)
These public values (A and B) are exchanged openly, meaning even an attacker can see them.
- Compute the Shared Secret
Now, both Alice and Bob use the received value and their own private number to compute the same shared secret:
• Alice computes:
S = (B^a) mod P
• Bob computes:
S = (A^b) mod P
Because of the way exponentiation works in modular math, both Alice and Bob end up with the same S, even though they never directly exchanged it!
Code Signing
Ensuring software integrity via digital signatures.
PKI
Public Key Infrastructure for managing digital certificates.
Certificate
A digital document that binds an entity with a public key.
Certificate Authority
An organization that issues digital certificates.
Intermediate CA
A CA with authority delegated by a higher CA.
OCSP
Online Certificate Status Protocol
Allows a host to query the status of a certificate.
Symmetric Encryption
Using the same key for both encryption and decryption.
ROT13
A simple substitution cipher shifting letters by 13 places.
Asymmetric Encryption
Using different keys for encryption and decryption.
In-band Exchange
Key exchange occurring over the same communication channel.
Out-of-band Exchange
Key exchange using a different communication channel.
Key Length
Longer keys provide better security but require more processing power.
Key Strength
Measure of encryption resistance to brute-force attacks.
Levels of Encryption (6)
- FDE, full disc encryption
- Partition-level encryption
- Volume level encryption
- File-level encryption.
- Database-level encryption.
- Record-level encryption
Hashing
One-way function ensuring data integrity.
Encryption
Two-way function ensuring data confidentiality.
Password Hashing
Securing stored passwords using hashing algorithms.
Collision
When different inputs produce the same hashed output, indicating weakness.
Hashing Algorithms
Common hashing functions. Produce a hash digest.
MD5
An older hashing algorithm prone to collisions.
SHA-256
A secure hashing function used widely in modern cryptography.
SHA-512
An advanced secure hashing function for high-security needs.
Salting
A way to add additional random characters to a password to make guessing it harder
