The Redmond, Wash., software giant normally releases security patches affecting its software products on the first Tuesday of the month unless a vulnerability is severe enough to warrant an immediate fix.
Two of the security bulletins set for release impact the Windows operating system, with an aggregate security rating of critical.
The third security bulletin affects a component with Microsoft Office. Companies will be able to automatically download the patches for all three security bulletins using the Microsoft Baseline Security Analyzer (MBSA).
The company said it would not be available through its Software Update Services site.
Microsoft also plans to release a non-security, high-priority update to Microsoft Office Tuesday, available through Microsoft Update and Windows Server Update.
The advisory, sent the Thursday prior to patch Tuesday, doesn't provide exact details of the security breaches prior to Patch Tuesday, in order to avoid tipping off malware writers. But the notice does give security managers a warning about which product lines are affected.
The security bulletins themselves could address several individual vulnerabilities, such as June's critical patch for Internet Explorer that dealt with both PNG images and XML redirects.
This article was first published on internetnews.com.