Information Security 

CompTIA Security+ Certification

The CompTIA Security+ certification shows employers that you’ve mastered the fundamental skills to perform essential cyber security functions and pursue a relevant career. Hence, the CompTIA Security+ exam focuses on the day-to-day real-time application of IT security knowledge at work.

You’ll need to answer at most 90 questions in this 90-minute examination and complete a survey after it ends. The passing score is 750 on a scale of 100–900.

The latest CompTIA Security+ exam code is SY0-601. The associated exam is available from November 2020 to sometime in 2023–2024. New topics include supply chain management and the Internet of Things (IoT).

Security+ Domains (SY0-601)

The following illustration shows the assessment criteria and the weighting in this examination:

CompTIA Security+ Domains (SY0-601)

This cheat sheet arranges concepts according to the subtopics in our Total Seminars Security+ course, and some topics span several Security+ domains. Hence, we’ve provided you a key to finding items according to Security+ domain:

HASHTAG (REMEMBER TO TYPE THE # SYMBOL)

DOMAIN (SY0-601)

#ATV

Attacks, Threats, and Vulnerabilities

#AD

Architecture and Design

#practical

Implementation

#op

Operations and Incident Response

#risk

Governance, Risk, and Compliance

Risk Management

The following topics pertain to real-life applications of cyber security. When you review the abbreviations, think: “Do I comprehend the ideas encapsulated by them?”

DOMAIN

CONCEPT

ELABORATION

#ATV

Threat Actor

Vulnerability exploiter

#ATV

TTP

(Adversary) tactics, techniques, and procedures

#ATV

Hacker

IT infrastructure penetrator

#ATV

Hacktivist

Politically motivated agent

#ATV

Script kiddie

Executor of pre-made programs

#ATV

Insider

Saboteur inside an organization

#ATV

Competitor/Rival

Saboteur outside an organization but in the same industry

#ATV

Shadow IT

IT systems deployed without the central IT department’s oversight

#ATV

Criminal syndicate (organized crime)

Profit-driven agent with intent to blackmail

#ATV

State actor

Foreign government agent

#ATV

APT

Advanced persistent threat: long-term intelligence-mining hacking

#ATV

OSINT

Open-source intelligence

• Government reports

• Media

• Academic papers

#ATV

CVEs

Common Vulnerabilities and Exposures

#ATV

AIS

Automated Indicator Sharing

#ATV

STIX

Structured Threat Information Expression

#ATV

TAXII

Trusted Automated Exchange of Intelligence Information

#risk

GDPR

General Data Protection Regulation

#risk

PCI DSS

Payment Card Industry Data Security Standard

#risk

ISO

International Organization for Standardization

#risk

CSA

Cloud Security Alliance

#risk

AV

Asset Value

#risk

EF

Exposure Factor

#risk

SLE

Single Loss Expectancy = AV × EF

#risk

ARO

Annualized Rate of Occurrence

#risk

ALE

Annualized Loss Expectancy = SLE × ARO

#risk

BIA

Business impact analysis

#risk

MTBF

Mean time between failures

#risk

MTTF

Mean time to failure

#risk

MTTR

Mean time to repair

#risk

RTO

Recovery time objective

#risk

RPO

Recovery point objective

#risk

Residual risk

Remaining risk after mitigation

#ATV #risk

Supply chain attack

Targets insecure elements in the supply chain

What do terms like “red team” and “blue team” mean in penetration testing?

The primary colors red, blue, and yellow refer to attackers, defenders, and builders of a system respectively. The secondary colors are combinations of these roles. For example, purple team members have dual attack/defense roles. The white team supervises the hack.

Cryptography

The following concepts are about obfuscating data from attackers and restoring them once they reach the intended destination.

DOMAIN

CONCEPT

ELABORATION

#ATV

Cryptographic attack/cryptanalysis

Finding weaknesses in the cryptosystem

#AD

Data at rest

On computer storage

#AD

Data in use/processing

In RAM being accessed

#AD

Data in transit/motion

Traveling along cables or broadcasting wirelessly

#AD

Symmetric cipher

Streaming:

• RC4

Block:

• DES

• Blowfish

• 3DES

Considerations:

• key length

• block size

• number of rounds

#AD

Asymmetric cipher

Examples:Diffie-Hellman key exchangeRSAElliptic-curve cryptography

#AD

Hashing

One-way, deterministic process of transforming a string of characters into another

#AD

Salting

Characters appended to a string (e.g., password) before hashing

#AD

Steganography

Hide data inside other data

#AD

Quantum

Exploit quantum mechanics

#AD

Post-quantum

Secure against cryptanalysis by quantum computer

#AD

Lightweight cryptography

Small footprint, low computational complexity

#AD

Homomorphic encryption

Makes performing operations on encrypted data possible

#AD #practical

CA

Certificate authority

#AD #practical

CRL

Certificate revocation list

#AD #practical

Stapling

Checks regularly for certificate invalidity

#AD #practical

Pinning

Associates certificate against known copy

#AD #practical

Trust model

• Direct

• Third-party

• Hierarchical

• Distributed

#AD #practical

Key escrow

Third party safeguarding private keys

#AD #practical

Certificate chaining

Top-down CA trust model

#AD #practical

Digital signature

Public key sender verified to own corresponding private key

#practical

P7B

√ certificate

√ chain certificates

✕ private key

#practical

P12

√ certificate

√ chain certificates

√ private key

#practical

PKI

Public Key Infrastructure

#practical

PKCS

Public Key Cryptography Standards

#ATV #AD

Brute-force attack

Trying character combinations

Variant: spraying (trying the same password across different accounts)

#ATV #AD

Dictionary attack

Using lists of probable passwords

#ATV #AD

Rainbow tables

Using pre-calculated password hashes

#ATV #AD

Key stretching

Method that strengthens weak passwords

Identity and Account Management

The following concepts deal with methods showing that you are the legitimate owner of an account.

DOMAIN

CONCEPT

ELABORATION

#practical #AD

Multi-factor Authentication (MFA)

Factors:

• Something you know

• Something you have

• Something you are

Attributes:

• Something you do

• Something you exhibit

• Someone you know

• Somewhere you are

#AD

Efficacy rate

• False acceptance

• False rejection

• Crossover error rate

#AD #practical

Access control schemes

• Attribute-based access control (ABAC)

• Role-based access control

• Rule-based access control

• MAC

• Discretionary access control (DAC)

• Conditional access

• Privileged access management

• Filesystem permissions

#practical

PAP

Password AuthenticationProtocol

#practical

CHAP

Challenge-HandshakeAuthentication Protocol

Example: MS-CHAP-v2

#practical

Sandboxing

Limiting access privileges of an application to minimize its impact on the rest of the system

#AD #practical

Identity federation

Delegate authentication to trusted third party

Tools of the Trade

We omit terminal commands because practice is more important than rote memorization for performance-based questions on Security+.

DOMAIN

CONCEPT

KEY POINTS TO REVIEW

#op

SPAN

Switch port analyzer

#op

IoC

Indicators of Compromise

#op

SNMP

Simple Network Management Protocol

#op

NXLog

Open-source log collection tool

#op #ATV

SIEM

Security Information and Event Management

Securing Individual Systems

The table below lists vital security concepts.

DOMAIN

CONCEPT

ELABORATION

#ATV

Malware

• Virus

• Polymorphic virus

• Fileless virus

• Worm

• Trojan

• Rootkit

• Keylogger

• Adware

• Spyware

• Ransomware

• Bots

• Remote access Trojan (RAT)

• Logic bomb

• Cryptomalware

• Potentially unwanted programs (PUPs)

• Command and control (C2/C&C)

• Keyloggers

• Backdoor

#ATV

Zero-day attack (ZDI)

Previously unknown vulnerability

#ATV

DNS Sinkholing

Give certain domain names invalid addresses

#ATV

Replay attack

Intercept data and replay later

#ATV

Pointer/object dereference attack

Using a null-value pointer as if its value is valid to bypass security logic

#ATV

Dynamic-link Library (DLL) injection

Force-run code in place of other code

#ATV

Resource exhaustion

Attacks using up bandwidth

Examples: DoS, DDoS

#ATV

Race conditions

Trying to perform two or more operations that should follow a proper order—clash

#ATV

Driver attacks

• Driver shimming

• Driver refactoring

#ATV

Overflow attacks

• Integer overflow

• Buffer overflow

#ATV #AD #practical

Securing hardware

• TPM

• Hardware redundancy

• UPS

• PDU

• Cloud redundancy

#practical

Securing endpoints

• Antivirus/Anti-malware

• EDR

• HIDS

• HIPS

• NGFW

• Allowlist/whitelist

• Block/deny lists,

• blacklist

#AD

Embedded system

Combination of hardware and software for a specific purpose

Examples:

• Raspberry Pi

• Field-programmable gate array (FPGA)

• Arduino

#AD

Specialized system

Combination of mechanical and digital interfaces for specific purposes

Examples:

• Medicine

• Aviation

• Smart meters

#AD

Internet of Things (IoT)

Network of physical devices

#AD

SCADA

Supervisory control and data acquisition

#AD

ICS

Industrial control system

The Basic LAN, Securing Wireless LANs, Securing Public Servers

We omit networking topics such as the above in this cheat sheet, and we encourage you to review them independently.

Physical Security

The best security measures are real-world limitations imposed on digital access. Here are a few concepts worth reviewing:

DOMAIN

CONCEPT

ELABORATION

#AD

Air gap

Physical isolation of secure computer network from unsecured networks

#AD

Protected cable distribution (Protected Distribution System)

Wired communications system with sufficient physical protection to carry unencrypted classified information without leakage

#AD

Screened subnet (demilitarized zone)

Five components:

• External network

• External router

• Perimeter network

• Internal router

• Internal network

#AD

Hot and cold aisles

Draw in cool air to equipment, and draw out hot air from equipment

#AD

Two-person integrity/control

Continuous monitoring by at least two authorized individuals, each capable of detecting incorrect or unauthorized security procedures

#AD

Secure data destruction

• Burning

• Shredding

• Pulping

• Pulverizing

• Degaussing

• Third-party solutions

#AD

Monitoring sensors

• Motion detection

• Noise detection

• Proximity reader

• Moisture detection

• Cards

• Temperature

Secure Protocols and Applications

This table excludes material overlapping with the Network+ exam objectives.

DOMAIN

CONCEPT

ELABORATION

#practical

S/MIME

Secure/Multipurpose Internet Mail Extensions

#ATV

Cross-site request forgery (CSRF/XSRF)

Hijack authenticated sessions

#ATV

Server-side request forgery (SSRF)

Cause servers to make outbound HTTP requests

#ATV

Cross-site scripting (XSS) attack

Inject malicious scripts into otherwise benign and trusted websites

#ATV #AD #practical

Injection attack

Affects:

• SQL

• LDAP

• XML

#ATV #AD #practical

Secure coding practices

• Input validation, sanitation

• Secure Web browser cookies

• HTTP headers

• Code signing

• Trusted components and APIs

#ATV #AD #practical

Software development life cycle (SDLC)

• Planning

• Defining

• Designing

• Building

• Testing

• Deployment

Testing Infrastructure

This section is about social engineering and penetration testing. Manipulating perception leads to much damage because humans are the weakest link in cyber security.

DOMAIN

CONCEPT

ELABORATION

#ATV

Social engineering

Principles (reasons for effectiveness):

• Authority

• Intimidation

• Consensus

• Scarcity

• Familiarity

• Trust

• Urgency

#ATV

Influence campaign

Propaganda:

• Hybrid warfare

• Social media

#ATV

Watering hole attack

Infect a trusted website

#ATV

Spam

Mass mailing of unsolicited messages

Variation: Spam over instant messaging (SPIM)

#ATV

Phishing

Attack by email; single target

#ATV

Smishing

Attack by SMS text message

#ATV

Vishing

Attack by telephone or voicemail

#ATV

Spear phishing

Attack by email; multiple targets

#ATV

Whaling

Phishing that targets high-ranking people, such as C-suite executives

#ATV

Invoice scam

Solicit payment from fraudulent invoice, often paired with whaling

#ATV

Dumpster diving

Recover information from trash

#ATV

Shoulder surfing

Look over someone’s shoulder, often with a recording device

#ATV

Tailgating

Unauthorized entity follows authorized party into secured premises

#ATV

Piggybacking

Tailgating with the authorized party’s consent

#ATV

Credential harvesting (farming)

Attacks to obtain credentials or personal information

#ATV

Pharming

Phishing + farming; making and redirecting users to a fake website

#ATV

Prepending

Adding username mentions to social media posts

#ATV

Pretexting

Digital gunpoint with the ransom being one’s private information

#ATV

Impersonation,identity fraud/theft

Attacks using stolen credentials or personal information

#ATV

Eliciting information

Strategic casual conversation without coercion to extract information from targets

#ATV

Reconnaissance

Covert information-gathering

#ATV

Hoax

False alarm

#ATV

Typosquatting

Attacks using mistyped web addresses

#ATV

Vulnerability scanning

Test for weaknesses

• Passive (monitoring)

• Active

◦ Credentialed

◦ Non‐credentialed

#ATV

Penetration testing (pentesting)

Actively exploit vulnerabilities

#ATV

Intrusive scan

Damage-causing pentesting

#ATV

Black box

Zero-knowledge pentesting

#ATV

White box

Extensive-knowledge pentesting

#ATV

Gray box

Partial-knowledge pentesting

#ATV #practical

Fuzzing

Input random characters and expect spurious results

#ATV

Pivot

Access network through vulnerable host—then attack

#ATV

Privilege escalation

Get administrator access

Dealing With Incidents

The following is a list of paradigms for handling, preventing, and mitigating cyber security breaches.

DOMAIN

CONCEPT

ELABORATION

#op

BCP

Business continuity plan

#op

COOP

Continuity of operations

#op #risk

DRP

Disaster Recovery Plan

#op

IRP

Incident Response Plan

#op

IoC

Indicators of Compromise

#op

Cyber Kill Chain Analysis

Trace steps of a successful hack

#op

MITRE ATT&CK Framework

Identify attacker techniques

#op

Diamond Model of Intrusion Analysis

Show how threat actors (adversaries) exploit capabilities in infrastructure against victims

#op #ATV

Security Orchestration, Automation, and Response (SOAR)

Automate incident responses, thus reducing response time

#AD #op

Legal hold

Process to preserve all forms of potentially relevant information for potential litigation

#AD #op

Chain of custody (CoC)

Paper trail of physical and electronic evidence

#AD #op

Disaster Recovery Sites

• Hot

• Warm

• Cold

#AD

RAID

Redundant array of inexpensive disks

#AD

UPS

Uninterruptiblepower supply

#AD

PDUs

Power distribution units

#AD

NAS

Network-attached storage

#AD

Multipath

Having multiple physical paths between devices

#AD

Network interface card (NIC) teaming

Physical network adapters grouped together

#AD

Load balancer

Distributes traffic across servers

#AD

Scalability

Ease of growing and managing increased demand on infrastructure

#AD

Backup types

• Full

• Copy

• Differential

• Incremental

• Snapshot

References: 

• https://github.com/MaheshShukla1/CompTIA-Security-Plus-SY0-701-Notes-CheatSheet-Exam-Prep/wiki/CompTia-Security--cheat-sheet-guide