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dba599 (Mark McKinnon) submits this review of Harlan Carvey's Windows Forensics and Incident Recovery, writing "This book takes an unusual approach to computer forensics in that it deals only with live analysis of the system: the compromised computer is left powered on and everything is running. (Compare to a dead analysis, for which the computer is powered off and the hard drive's contents are then analyzed.)" Read on for the rest of McKinnon's review. Windows Forensics and Incident Recovery author Harlan Carvey pages 460 publisher Addison Wesley rating 9 reviewer Mark McKinnon ISBN 0321200985 summary Forensic analysis and incident recovery on a live Microsoft Windows is explained for the system administrator, security administrator and knowledgeable home user.

The intended audience, according to the author, is "anyone with an interest in Windows security, which includes Windows system and security administrators, consultants, incident response team members, students and even home users." The author assumes the reader is familiar with basic networking (including TCP/IP) and has some Windows administration skills. Some programming ability, though not actually required, will help out greatly with reading and understanding the many examples provided, and will let you make your own modifications (this is encouraged by the author throughout the book).

The chapter on data hiding was a real eye-opener -- it's amazing the things Microsoft has implemented as part of the operating system (and included applications) that can be used to hide things. Discovering the hidden information is talked about, as well how it is hidden. Sample topics include file attributes, alternate data streams, OLE and stenography. This is an excellent chapter with many examples; I found myself stopping after each subject to try out each of the discussed techniques.

The next chapter delves into incident preparation. Carvey addresses some of the things that administrators can do to harden their systems. He goes over the application of security policies in general, as well as intelligent assignment of file permissions. He then covers Windows File Protection and how it is implemented, and includes a perl script to implement your own file watcher. He touches briefly on patch management and anti-virus programs, then moves into monitoring. He provides quite a few scripts, and discusses other means by which you can monitor your system.

The next chapter describes tools that can be used in incident response. This chapter has quite a lot of information and took me the longest to get through, because of all the tools mentioned that I had to download and check while I was reading the book. Carvey uses a mixture of his own perl scripts and programs that can be downloaded from places like Sysinternals, Foundstone, DiamondCS and others. All of the tools used are open source (or are at least freely available). That equips the reader with a low-cost toolkit, especially important to the home user or small business owner who cannot afford to buy the commercial equivalent. Carvey does acknowledge, though, that there are quite a few commercial tools with great functionality out there.

The first part of the incident-response tools chapter deals with the collection of volatile information (processes, services, etc.); this is a vital part of live analysis. The second part deals with the collection of non-volatile information (the content of the Windows registry, file MAC times and hashes, etc.) and tools for analyzing files. Carvey also shows how some of the tools complement each other, and that there is not one almighty tool that will find all the data you need. (This is also proven by example in a later chapter when he talks about rootkits.)

The next chapter deals with developing a security methodology, and it's handled differently than in most books: the author presents the material as a series of dreams that a Windows system administrator has, showing how an individual can come up with and fine tune a methodology as incidents happen. Carvey has used this approach before in a series of articles entitled "No Stone Unturned" for SecurityFocus.com, and the creative approach appeals to me. As he moves from dream to dream, you can relate to the admin's circumstances (and mistakes), and how be and becomes better at responding to different incidents.

The next chapter talks about what to usefully look for with the tools the book has introduced. It discusses infection vectors, types of malware and rootkits, and demonstrates tools and techniques for detecting them. This is where the author makes a clear point of why you would need to run several different tools, even if some overlap. His example uses an installed rootkit; running a particular program from a previous chapter, he shows that it fails to find that anything untoward is running -- it takes another program from the same chapter to actually reveal the rootkit's presence. By cross referencing the output for both programs, you can see why you should run more then one type of analysis tool for certain areas to make sure you are not missing anything.

Finally, the author dedicates an entire chapter to his own Forensic Server Project, a two-pronged approach to live forensic analysis which uses two machines simultaneously. The first piece, the Forensic Server Module, is the listener software; this runs on a clean PC where the data will be sent from the compromised system. The other piece, called the First Responder Utility, runs several of the programs and scripts from the incident tools chapter on the compromised system . After installing everything needed for both parts of this system, I followed the author's instructions on how to run it. What a slick tool! I ran it from a couple of PCs on my home network and was able to get a lot of the information that was described in the book as well as hash values for each log file that was produced, and a general log of everything the First Responder Unit did. The whole principle of this is that when you have an incident there will be very little interaction with the compromised system, since everything is scripted to begin with.

The framework that this software constitutes is very flexible. I was able to add two new features to the Forensic Server Module and the First Responder Utility with very little code. The first addition I made was to mark all the logs as read-only on the file system after they were written from the Forensic Server module. The next addition I made was to add a perl script to scan the c:\ drive of the PC that the First Responder Utility was running on. After I made both additions, I tested everything out, and it worked great. I had my extra log files and they were all read-only. My hat goes off to the author for coming up with and including this in the book, a really nice piece of software.

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