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Understand how to safeguard data and control access in this comprehensive guide on core security principles and techniques. Learn about confidentiality, integrity, availability, and key security goals such as steganography, hashing, digital signatures, and more. Discover strategies for maintaining data integrity and ensuring non-repudiation. Enhance your knowledge of authentication, authorization, and risk mitigation approaches in the cybersecurity realm. 8 Relevant
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Ch 1: Mastering Security Basics CompTIA Security+: Get Certified Get Ahead: SY0-401 Study Guide Darril Gibson
The CIA of Security Confidentiality Integrity Availability
Confidentiality • Prevents unauthorized disclosure of data • Ensures that data is only viewable by authorized users • Such as Personally Identifiable Information (PII) • Some methods • Encryption • Ex: Advanced Encryption Standard (AES) • Access controls
Access Controls • Identification • Username: Who are you? • A claim, not proof • Authentication • Proof of identity • Often by providing a password • Authorization • Granting access to resources
Steganography • Hiding data within other data • Ex: a secret message inside an image • "Hiding data in plain sight" • Observers won't even know a message is being sent
Integrity • Assures that data has not been modified, tampered with, or corrupted • Only authorized users should modify data • Hashing assures integrity • Hash types: MD5, SHA-1, HMAC • If data changes, the hash value changes
Digital Signatures • Makes a legal agreement • Like a handwritten signature • Provides authentication • Also provides non-repudiation
Non-Repudiation • Prevents entities from denying that they took an action • Examples: signing a home loan, making a credit card purchase • Techniques • Digital signatures • Audit logs
Certificates and PKI (Public Key Infrastructure) • Certificates prove the identity of a server or user • Contain encryption keys • Certificates are managed by the PKI • A group of companies that issue and verify certificates • Analogous to credit card companies
Availability • Data and services are available when needed • Remove SPOF (Single Point of Failure)
Availability • Techniques: • Disk redundancies (RAID) • Server redundancies (clusters) • Load balancing • Site redundancies • Backups • Alternate power • Cooling systems
Balancing CIA • You can never have perfect security • Increasing one item lowers others • Increasing confidentiality generally lowers availability • Example: long ,complex passwords that are easily forgotten
Patching • Software requires frequent updates • Patch Management • Testing patches to make sure they aren't harmful • Deploying them to all devices
Safety • Safety of people • Escape plans and routes for fire, earthquake, etc. • Drills and training • Safety of assets • Physical security controls • Fences, lighting, locks, CCTV (closed-circuit television) systems
Fail-Open • When power fails, exit doors commonly fail in an open state • So people aren't trapped inside • This lowers safety of material assets, but increases safety of people
Defense in Depth • Layers of protection • Example • Firewall • Antivirus • Deep Freeze
Risk • Risk • The likelihood of a threat exploiting a vulnerability, resulting in a loss • Threat • A circumstance or event that has the potential to compromise confidentiality, integrity, or availability • Insider threat • Vulnerability • A weakness
Risk Mitigation • Reduces chance that a threat will exploit a vulnerability • Done by implementing controls (also called countermeasures and safeguards) • Even if a threat can't be prevented, like a tornado • Risk can still be reduced with controls, like insurance, evacuation plans, etc.
Controls • Access controls • After Authentication, only authorized users can perform critical tasks • Business continuity and Disaster Recovery Plans • Reduce the impact of disasters • Antivirus software • Reduces the impact of malware
Identification, Authentication, and Authorization • Identification • State your name (without proving it) • Authentication • Proves your identity (with a password, fingerprint, etc.) • Authorization • Grants access to resources based on the user's proven identity
Identity Proofing • Verifying that people are who they claim to be prior to issuing them credentials • Or when replacing lost credentials
Sarah Palin's Email • Link Ch 1a
Five Factors of Authentication • Something you know (weakest) • Such as a password • Something you have • Such as a smart card • Something you are (strongest) • Such as a fingerprint • Somewhere you are • Such as geolocation • Something you do • Such as gestures on a touch screen
Password Rules • Passwords should be strong • At least 8 characters, with three of: uppercase, lowercase, numbers, and symbols • Change passwords regularly • Verify a user's identity before resetting a password • Don't reuse passwords • Implement account lockout policies • Change default passwords
Password Rules • Don't write down passwords • Don't share passwords
Password Rules • Password history • Remembers previous passwords so users cannot re-use them • Account Lockout Policies • Account lockout threshold • The maximium number of times a wrong password can be entered (typically 5) • Account lockout duration • How long an account is locked (typically 30 min.)
Previous Logon Notification • Gmail has it, at the bottom of the screen
Creating Strong Passwords • At least 8 characters long • Isn't in a dictionary • Contains three of these character types: • Uppercase letters A-Z • Lowercase letters a-z • Numbers 0-9 • Special characters like @#$%
Changing Default Passwords • Many devices have default passwords • Like routers • These must be changed before use • "Hardening"
Something You Have • Smart Card • Contains a certificate • Read by a card reader • Image from made-in-china.com/
Smart Cards • Embedded certificate • Public Key Infrastructure • Allows issuance and management of certificates • CAC (Common Access Card) • Used by US Department of Defense • PIV (Personal Identity Verfication) card • Used by US federal agencies
Something You Have • Token or Key Fob • Image from tokenguard.com • HOTP (HMAC-based One-Time Password) • Open standard using a secret key and an incrementing counter • HMAC hash used to create 6- or 8-digit value • Password remains valid till it is used • TOTP (Time-based One-Time Password) • Uses a timestamp instead of a counter • Password expires every 30 seconds
Something You Are (Biometrics) • Fingerprint, handprint, palm scanner • Image from amazon.com • Retinal scanners • Uncomfortable for some people • Iris scanners • Easier to use
False Acceptance and False Rejection • False Acceptance Rate • Incorrectly identifying an unauthorized user as authorized • False Rejection Rate • Incorrectly rejecting an authorized user
Somewhere You Are • IP address • Gives general location • May block logins from unexpected nations • MAC address • Identifies a specific device
Something You Do • Windows 8 picture passwords • Gestures such as tapping or drawing lines • Keystroke dynamics when typing • Also called "behavioral biometrics"
Multifactor Authentication • More than one of • Something you know • Something you have • Something you are • Two similar factors is not two-factor authentication • Such as password and PIN
Authentication Services • Kerberos • Used in Windows Active Directory Domains • Used in UNIX realms • Developed at MIT • Prevents Man-in-the-Middle attacks and replay attacks
Kerberos Requirements • A method of issuing tickets used for authentication • Key Distribution Center (KDC) grants ticket-granting-tickets, which are presented to request tickets used to access objects • Time synchronization within five minutes • A database of subjects or users • Microsoft's Active Directory
Kerberos Details • When a user logs on • The KDC issues a ticket-granting-ticket with a lifetime of ten hours • Kerberos uses port 88 (TCP & UDP) • Kerberos uses symmetric cryptography
LDAP (Lightweight Directory Access Protocol) • Formats and methods to query directories • Used by Active Directory • An extension of the X.500 standard • LDAP v2 can use SSL encryption • LDAP v3 can use TLS encryption • LDAP uses ports 389 (unencrypted) or 636 (encrypted) (TCP and UDP)
Single Sign-On • Users can access multiple systems after providing credentials only once • Federated Identity Management System • Provides central authentication in nonhomogeneous environments
SSO and Transitive Trusts • Parent domain trusts two child domains • Training and Blog • Therefore the two child domains trust one another • This is called a Transitive Trust