Amongst those six bulletins, four are rates as critical, the higher level on Microsoft’s security rating system.

When a vulnerability is rated as critical means that that a system can be compromised remotely with little interaction required by the user.

Specifically, Windows XP Service Pack 2, Windows Server 2003, IE 5.01 running on Windows 2000 with

SP4, Outlook Express and Windows Mail in Vista are among the affected software.

The two non-critical security holes affect Vista and Visio 2002 and are respectively rated 'moderate' and 'important'.

This was the first early warning in the new more detailed format that Microsoft promised last month when it said customers asked for additional information to plan their patching schedules.

Each of the six expected updates was recapped with short description, severity rating, description of potential impact, whether the Baseline Security Analyser will detect patch need, and the affected software.