Learn To Be Least

An administrator accidentally downloads malicious code while surfing the Web. A Windows developer writes code that requires Administrator privileges to work properly. These dangerous practices violate one of security's most fundamental concepts: the principle of least privilege. This principle states that you should give a user or a piece of code only the privileges it needs to do the job--nothing less, and certainly nothing more. Malicious code can do much more harm when it can execute in the security context of a highly privileged account, and highly privileged processes can do much more harm when compromised (or simply buggy).

Least privilege has long been a well-respected and supported principle in the UNIX world, but Microsoft started taking it seriously only with the release of Windows XP and Windows 2000. Support for the Least-Privileged User Account (LUA) is a key security theme of Microsoft Vista (formerly code-named Longhorn), but for now, XP and Win2K provide several tools that you can use to honor least privilege. Use these tools to run Windows processes and applications from an LUA or non-administrator account--and put security first. . . .