CHAPTER 1
Overview
• What is Computer Security?
• Computer Security protection afforded to an automated information
system in order to attain the applicable objectives of preserving the
integrity, availability and confidentiality of information system
resources (includes hardware,software, firmware, information/data,
andtelecommunications).
Introduction
• Traditional IT Infrastructure
• Modern IT Infrastructure
• Modern IT Infrastructure Security
• Cyber Attacks
• Vulnerabilities
• Defence Strategies & Techniques
• Authentication Methods
Password Based Authentication
Token Based Authentication
Biometric Authentication
Access Control Policies & Models
Terminologies used in Acesss Control Policies
Acess Control Policies
Authentication and Acess Control Services
• Cyber-attacks, Vulnerabilities, Defense Strategies and
• Techniques, Authentication Methods- Password, Token
• and Biometric, Access Control Policies and Models
• (DAC,MAC, RBAC, ABAC, BIBA, Bell La
• Padula),
Traditional information Technology infrastructure
Data
Management Technology
Hardware Technology Services
Software
applications Network
IT
Infrastructure
Components
Modern IT Infrastructure
• Cloud Platforms
• Wireless Network
• Cloud Based Storage
• Heterogenous Devices
Stages of Attack
Attackers Techniques
• Malware
• Phishing
• Denial of Service
• Man in the Middle
• SQL Injection
• Zero day exploit
Vulnerabilities
Intrusion Activites
• Can you name some intrusion activities?
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Computer Security Challenges
• not simple
• must consider potential attacks
• procedures used counter-intuitive
• must decide where to deploy mechanisms
• involve algorithms and secret info
• battle of wits between attacker / admin
• not perceived on benefit until fails
• requires regular monitoring
• too often an after-thought
• regarded as impediment to using system
Vulnerabilities and Attacks
• system resource vulnerabilities may
• be corrupted (loss of integrity)
• become leaky (loss of confidentiality)
• become unavailable (loss of availability)
• attacks are threats carried out and may be
• passive
• active
• insider
• outsider
Defence Strategies & Techniques
• Authentication
• Authorization
• Accounting
Authentication Methods
• assword Based Authentication
P
• Password Security Mechanisms
Encrypted Passwords
One- way cryptographic hash function
Salt Value
Password Cracking Attacks
Dictionary Attack
Brute Force Attack
Rainbow Table Attack
Phishing Attack
Malware Attack
Shoulder Surting Attack
Spidering
Policies to choose passwords
Token Based Authentication
• Static Authentication
• Dynamic Authentication
• Challenge Response
• Types of Tokens
Memory Cards
Smart Cards
Working of a Smart Card
Types of Smart Card
Contact Smart Cards
Contactless Smart Cards
Dual Interface Cards
Hybrid Smart Cards
Memory Smart Cards
Microprocessor Smart Cards
Biometric Authentication
• Types of Biometric
Authentication
Physiological Biometrics
• Facial Recognition
• Fingerprint Scanning
• Finger Vein ID
• Hand Geometry
• Retina Scan
• Iris Recognition
• DNA
Behavioral Biometrics
• Keystoke Recognition
• Signature Recognition
• Voice Recognition
Process of Biometric Authentication
• Enrolment of User
• Verification of User
Access Control Policies and Models
• Terminologies Used in Access Control Policies
Subject
owner
Group
World
Object
Access Rights
Read
Write
Execute
Delete
Create
Search
• Acess Control Policies
Mandatory Access Control
Process of ABAC
Bell Lapadula lattice
Biba Lattice
Who launch attacks
• Can you name some?
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• And?
Motivation of an attack
• Try to give me some reason
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• Else?
Taxonomy of Attacking
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• ??????, ??????(telnet, ftp, web)???
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• Backdoor, trojan horse, sniffer
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• Rootkit
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Target of Attackers
• ???? IP addresses
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• ??, e-mail, ??????, ?????????(DNS)??,
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Collect Target Information
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• ????(yahoo, google, dogpile, altivista, edgar)
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Password Cracking
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• Brutus, http//www.hoobie.net/brutus/brutus-downlo
• ad.html
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Homework
• Use __ to scan your computer, and find out
• the vulnerabilities in the computer
• Read the __report, and write a report to me
• to show me what you learned from the ___report
• Your report needs a cover page which includes
Countermeasures
• means used to deal with security attacks
• prevent
• detect
• recover
• may result in new vulnerabilities
• will have residual vulnerability
• goal is to minimize risk given constraints
Security Mechanisms/Tools
• ????????
• R-scanner
• nessus
• ????
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Security Scanner
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• R-scanner, nessus
• ??????
• NASL (Nessus Attack Scripting Language)
Firewall
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What the firewall cant
• ?????????????
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Intrusion Detection System
• ?????????
• Snort
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• Agent based IDS
• ??????????
Threat Consequences
• unauthorized disclosure
• exposure, interception, inference, intrusion
• deception
• masquerade, falsification, repudiation
• disruption
• incapacitation, corruption, obstruction
• usurpation
• misappropriation, misuse
Network Security Attacks
• classify as passive or active
• passive attacks are eavesdropping
• release of message contents
• traffic analysis
• are hard to detect so aim to prevent
• active attacks modify/fake data
• masquerade
• replay
• modification
• denial of service
• hard to prevent so aim to dete
Security Functional Requirements
• technical measures
• access control identification authentication
• system communication protection system
• information integrity
• management controls and procedures
• awareness training audit accountability
• certification, accreditation, security
• assessments contingency planning maintenance
• physical environmental protection planning
• personnel security risk assessment systems
• services acquisition
• overlapping technical and management
• configuration management incident response
• media protection
Computer Security Strategy
• specification/policy
• what is the security scheme supposed to do?
• codify in policy and procedures
• implementation/mechanisms
• how does it do it?
• prevention, detection, response, recovery
• correctness/assurance
• does it really work?
• assurance, evaluation
Homework
• Get an exploit
• Attack a target in our testbed.
• Use Snort to detect the attack and Use etheral to
• analyse the communications between the attacking
• and victim hosts.
• Write the analysis report
