Microsoft: It's patch time of the month again

As part of its monthly patching cycle, Microsoft plans to release three security alerts on Tuesday for flaws in Windows and Office.

Two of the security bulletins apply to Windows, and at least one of them is deemed "critical", Microsoft's highest risk rating, the company said in a notice posted on its website on Thursday. Its Office productivity suite will get one bulletin, also rated critical.

The notice did not specify whether one of the patches will be for Internet Explorer. Microsoft earlier this week offered a workaround for a known flaw in the web browser that opens the door for intruders to crash IE and run arbitrary code.

Microsoft said it will also issue a "high-priority" update for Office that is unrelated to security on Tuesday. In addition, that day is tagged for the release of an updated version of the Windows Malicious Software Removal Tool, which detects and removes malicious code placed on computers, the company said.

The company gave no further information on Thursday's bulletins, other than stating that some of the Windows fixes will require restarting the computer, as may the Office update.

The Redmond, Washington, software giant provides information in advance of its monthly patch release day, which is every second Tuesday of the month, so people can prepare to install the patches. In June, Microsoft released 10 security bulletins.

It rates as critical any security issue that could allow a malicious internet worm to spread without any action required on the part of the user.

Microsoft has set a time of Wednesday at 11:00(PDT) to host a webcast about the new fixes.

Joris Evers writes for CNET News.com