A second UAC security flaw in the Windows 7 beta’s (download) default security configuration allows a malicious application to autonomously elevate themselves to full administrative privileges without UAC prompts or turning UAC off. By default Windows 7 ships with UAC configured at the “Notify me only when programs try to make changes to my computer.” level. As the UAC helper text indicates, “this setting does not prompt when you change Windows settings, such as control panel and administration tasks.”

Windows 7 has the ability automatically elevates Microsoft-signed applications and code which specifies “auto elevation” to mitigate the number of UAC prompts.

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