firewalls & network security with intrusion detection and vpns, 2 nd edition chapter 1...

FIREWALLS & NETWORK SECURITY with Intrusion Detection and VPNs,

2nd Edition

Chapter 1Introduction to

Information Security

Firewalls & Network Security, 2nd ed. - Chapter 1 Slide 2Firewalls & Network Security, 2nd ed. - Chapter 1

Learning Objectives

Upon completion of this chapter, you should be able to: Explain the relationship among the component parts of information

security, especially network security Define the key terms and critical concepts of information and

network security Describe the organizational roles of information and network

security professionals Understand the business need for information and network security Identify the threats posed to information and network security, as

well as the common attacks associated with those threats Differentiate threats to information within systems from attacks

against information within systems

Firewalls & Network Security, 2nd ed. - Chapter 1

Introduction

Firewalls and network security are critical components in securing day-to-day operations of nearly every organization in business today

Before learning to plan, design, and implement firewalls and network security, it is important to understand the larger topic of information security and how these two components fit into it

What Is Information Security?

Information security (InfoSec) is defined by standards published by CNSS as the protection of information and its critical elements, including the systems and hardware that use, store, and transmit that information

To protect information and related systems, organizations must implement policy, awareness training and education, and technology

Firewalls & Network Security, 2nd ed. - Chapter 1 Slide 4


Figure 1-1Components of Information Security

What is Information Security? (continued) C.I.A. triangle consists of Confidentiality, Integrity,

and Availability List of characteristics has expanded over time,

but these three remain central Successful organization maintains multiple layers

of security:– Network security

– Physical security

– Personal security

– Operations security

– Communications securityFirewalls & Network Security, 2nd ed. - Chapter 1 Slide 6


Critical Characteristics of Information

Availability enables authorized users to access information without interference or obstruction and to receive it in required format

Accuracy means information is free from error and has the value the end user expects

Authenticity is quality or state of being genuine or original, rather than reproduced or fabricated; information is authentic when it is what was originally created, placed, stored, or transferred

Critical Characteristics of Information (continued)

Confidentiality is when information is protected from exposure to unauthorized entities

Integrity is when information remains whole, complete, and uncorrupted

Utility of information is quality or state of having value for some end purpose; information must be in a format meaningful to end user

Possession is ownership or control of some object or item; information is in one’s possession if one obtains it, independent of format or other characteristics



Figure 1-2 The CIA Triad and the McCumber Cube

Securing Components

When computer is subject of an attack, it is used as active tool to conduct attack

When computer is object of an attack, it is entity being attacked

Direct attack is when hacker uses a computer to break into a system

Indirect attack is when a system is compromised and used to attack other systems, such as a botnet or other distributed denial-of-service attack


Figure 1-3 Computer as the Subject and Object of an Attack


Balancing Information Access and Security

Information security cannot be an absolute; it is a process, not a goal

Information security should balance protection and availability

To achieve balance—to operate information system to satisfaction of users and security professionals—level of security must allow reasonable access, yet protect against threats


Security Professionals and the Organization

Chief Information Officer– Senior technology officer

– Primarily responsible for advising senior executive(s) for strategic planning

Chief Information Security Officer– Individual primarily responsible for assessment,

management, and implementation of securing information in the organization

– May also be referred to as Manager for Security, Security Administrator, or a similar title


Security Professionals and the Organization (continued)

Information security project team should consist of individuals experienced in one or more facets of vast array of technical and nontechnical areas:ChampionTeam leaderSecurity policy developersRisk assessment specialistsSecurity professionals System, network, and storage administratorsEnd usersFirewalls & Network Security, 2nd ed. - Chapter 1 Slide 14

Firewalls & Network Security, 2nd ed. - Chapter 1 15

Data Ownership

Data owner: responsible for the security and use of a particular set of information

Data custodian: responsible for the storage, maintenance, and protection of the information

Data users: the end systems users who work with the information to perform their daily jobs supporting the mission of the organization

Threats

Sun Tzu Wu: “If you know the enemy and know yourself, you

need not fear the result of a hundred battles. If you know yourself but not the enemy, for

every victory gained you will also suffer a defeat.

If you know neither the enemy nor yourself, you will succumb in every battle.”


Threats (continued)

To make sound decisions about information security, management must be informed about the various threats facing the organization, its people, applications, data, and information systems—that is, the enemy

In the context of information security, a threat is an object, person, or other entity that represents a constant danger to an asset


Threats (continued)



Figure 1-5 Human Error or Failure


Figure 1-6 Shoulder Surfing


Figure 1-7 Hacker Profiles


Espionage or Trespass (continued)

Generally two skill levels among hackers:– Expert hacker

• Develops software scripts and codes exploits• Usually a master of many skills• Often creates attack software to share with others

– Unskilled hackers (script kiddies)• Hackers of limited skill• Use expert-written software to exploit a system• Do not usually fully understand systems they hack

Espionage or Trespass (continued)

Other terms for system rule breakers:– Cracker: “cracks” or removes protection

designed to prevent unauthorized duplication

– Phreaker: hacks the public telephone network

Slide 23Firewalls & Network Security, 2nd ed. - Chapter 1


Information Extortion

Information extortion is an attacker or formerly trusted insider stealing information from a computer system and demanding compensation for its return or non-use

Extortion found in credit card number theft


Software Attacks

When an individual or group designs software to attack systems, they create malicious code called malware

Designed to damage, destroy, or deny service to target systems

Includes:– Virus (macro virus or boot virus )– Worms – Trojan horses– Back door or trap door– Polymorphic– Virus and worm “hoaxes”


Figure 1-8 Trojan Horse Attack


Forces of Nature

Forces of nature, force majeure, or acts of God are dangerous because they are unexpected and can occur with very little warning

Can disrupt not only the lives of individuals, but also the storage, transmission, and use of information

Include fire, flood, earthquake, and lightning as well as electrostatic discharge

Since it is not possible to avoid many of these threats, management must implement controls to limit damage and also prepare contingency plans for continued operations


Deviations in Quality of Service

Situations of product or services not delivered as expected

Information system depends on many inter-dependent support systems

Service issues that dramatically affect the availability of information and systems include:– Internet service

– Communications service

– Power irregularities


Power Irregularities

Power irregularities are common and lead to fluctuations such as:– Spike: momentary increase– Surge: prolonged increase– Sag: momentary low voltage– Brownout: prolonged drop– Fault: momentary loss of power– Blackout: prolonged loss

Electronic equipment is susceptible to fluctuations; controls can be applied to manage power quality


Malicious Code

This kind of attack includes the execution of viruses, worms, Trojan horses, and active Web scripts with the intent to destroy or steal information

The state of the art in attacking systems is the multi-vector worm using up to six attack vectors to exploit a variety of vulnerabilities in commonly found information system devices


Table 1-2 Attack Replication Vectors

New Table


Attack Descriptions

“Hoaxes”: a more devious approach to attacking computer systems is transmission of a virus hoax, with a real virus attached

Back doors: using a known or previously unknown and newly discovered access mechanism, an attacker can gain access to a system or network resource

Password crack: attempting to reverse calculate a password


Attack Descriptions (continued)

Brute force: the application of computing and network resources to try every possible combination of options of a password

Dictionary: the dictionary password attack narrows the field by selecting specific accounts to attack and uses a list of commonly used passwords (the dictionary) to guide guesses



Denial-of-service (DoS): attacker sends a large number of connection or information requests to a target; so many requests are made that the target system cannot handle them successfully along with other, legitimate requests for service– May result in a system crash or merely an

inability to perform ordinary functions Distributed denial-of-service (DDoS): attack in

which a coordinated stream of requests is launched against a target from many locations at the same time


Figure 1-9 Denial-of-Service Attacks



Spoofing: technique used to gain unauthorized access whereby the intruder sends messages to a computer with an IP address indicating that the message is coming from a trusted host

Man-in-the-Middle: in this attack, an attacker sniffs packets from the network, modifies them, and inserts them back into the network; also called TCP hijacking

Spam: unsolicited commercial e-mail; while many consider spam a nuisance rather than an attack, it is emerging as a vector for some attacks


Figure 1-10 IP Spoofing


Figure 1-11 Man-in-the-Middle



Mail-bombing: another form of e-mail attack that is also a DoS, in which an attacker routes large quantities of e-mail to the target

Sniffer: program and/or device that can monitor data traveling over a network; can be used for both legitimate network management and for stealing information from a network

Social engineering: within the context of information security, the process of using social skills to convince people to reveal access credentials or other valuable information



“People are the weakest link. You can have the best technology; firewalls, intrusion-detection systems, biometric devices ... and somebody can call an unsuspecting employee. That's all she wrote, baby. They got everything.”

“Brick attack”: the best configured firewall in the world can’t stand up to a well-placed brick



Buffer overflow: application error occurs when more data is sent to buffer than it can handle; when buffer overflows, attacker can make target system execute instructions or attacker can take advantage of some other unintended consequence of the failure

Timing attack: relatively new, works by exploring contents of Web browser’s cache; can allow collection of information on access to password-protected sites– Another attack by the same name involves

attempting to intercept cryptographic elements to determine keys and encryption algorithms

Chapter Summary

Firewalls and network security are essential components for securing systems that businesses use to run day-to-day operations

Information security is protection of information and its critical elements, including systems and hardware that use, store, and transmit that data

C.I.A. triangle based on confidentiality, integrity, availability of info and systems that process it

CNSS Security model (McCumber Cube) provides graphical description of approach used in computer and information security

Firewalls & Network Security, 2nd ed. - Chapter 1 42

Chapter Summary (continued)

Computer can be subject of attack or object of attack; two types of attacks: direct and indirect

Information security not an absolute: a process, not a goal; should balance reasonable access and availability while protecting against threats

Information security performs four functions:– Protects organization’s ability to function

– Enables safe operation of applications implemented on organization’s IT systems

– Protects data that organization collects and uses

– Safeguards technology assets of organizationFirewalls & Network Security, 2nd ed. - Chapter 1 Slide 43


Requires wide range of professionals and skill sets to support information security program

Information security project team includes: team leader, security policy developers, risk assessment specialists, security professionals, systems, network and storage administrators, and end users

Three types of data ownership: data owner, data custodian, and data user

Threat is object, person, or other entity that represents a constant danger to assets



Attack is deliberate act or action that takes advantage of vulnerability to compromise controlled system

Vulnerability is identified weakness in controlled system

Major types of attacks include: malicious code, “hoaxes” of malicious code, back doors, password cracking, DoS, DDoS, spoofing, man-in-the-middle, spam, mail bombing, sniffers, social engineering, buffer overflow, and timing attacks


firewalls & network security with intrusion detection and vpns, 2 nd edition chapter 1...

Documents

information security

network security professionals

protection of information

fabricated information

multiple layers of security

transferred slide

end purpose information

introduction firewalls