Linux Server Security, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 1: Threat Modeling and Risk Management

Components of Risk

Simply put, risk is the relationship between your assets, the vulnerabilities character-

istic of or otherwise applicable to those assets, and attackers who wish to steal those

assets or interfere with their intended use. Of these three factors, you have some

degree of control over assets and their vulnerabilities. You seldom have control over

attackers.

Risk analysis is the identification and evaluation of the most likely permutations of

assets, known and anticipated vulnerabilities, and known and anticipated types of

attackers. Before we begin analyzing risk, however, we need to discuss the compo-

nents that it comprises.

Assets

Just what are you trying to protect? Obviously you can’t identify and evaluate risk

without defining precisely what is at risk.

This book is about Linux security, so it’s safe to assume that one or more Linux sys-

tems are at the top of your list. Most likely, those systems handle at least some data

that you don’t consider to be public.

But that’s only a start. If somebody compromises one system, what sort of risk does

that entail for other systems on the same network? What sort of data is stored on or

handled by these other systems, and is any of that data confidential? What are the

ramifications ...