Advanced Security Options
The 11 steps outlined in the previous sections apply to every Windows user. The suggestions in this section include steps that aren't essential but might be useful to advanced users or those with special configurations.

Configure Windows Explorer to show all file name extensions Some viruses and Trojan horse programs use a cheap trick to try to slide past a Windows user's defenses, adding a second, innocent-looking file name extension to disguise the true executable extension. In a default Windows installation, extensions are hidden. As a result, a file with the name Letter.doc.vbs will appear to a casual user as Letter.doc. Sophisticated Windows users will have no trouble seeing through this trick, but a less experienced or distracted user might be fooled long enough to launch a dangerous file. To protect yourself, open Windows Explorer and choose Tools, Folder Options. On the View tab, clear the Hide Extensions For Known File Types box, as shown in Figure 2-13.


Figure 2-13. Display all file name extensions so that you can more easily detect hostile software that tries to hide its true extension.
For a discussion of how hostile software uses multiple file name extensions to attack Windows, see Identifying Malicious Software.

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Selectively show extensions

If you can't stand the clutter caused by the full display of file name extensions, you can customize specific file types so that their extensions are always visible, while still keeping other, less dangerous extensions hidden. If you're concerned about files with the .vbs, .pif, and .scr extensions, for instance, you can ensure that those extensions are always visible by following the steps outlined in Blocking Dangerous Attachments. You can also use a custom script to toggle the display of file name extensions and hidden folders as needed; the CD included with Microsoft Windows XP Inside Out includes one such script, called ToggleHiddenExplorerStuff.

Adjust Internet Explorer security options The zone-based security settings in Internet Explorer 6 provide excellent protection against most garden-variety attacks. Advanced security options allow you to significantly increase the level of security in your browser. We explain these options in full in Chapter 8, "Making Internet Explorer Safer."

Adjust Internet Explorer privacy options Are you concerned that browser cookies are disclosing too much information about you? Internet Explorer 6 uses a fairly complex system to control the information that flows between you and Web sites. You can customize these settings significantly by using the built-in privacy controls in Internet Explorer 6, shown here. If you're willing to roll up your sleeves and work with XML files, you can create and share custom privacy settings as well, as we document in Setting Cookie Preferences in Internet Explorer 6.

Libellés : Advanced, Options, Security