Tomorrow will be one of the busiest days of the month for IT security professionals updating their anti-malware protection.

For its April Patch Tuesday release, Microsoft will distribute five new security fixes, including one for the infamous createTextRange() vulnerability for Internet Explorer (IE).

Four of thesecurity updates will affect Microsoft Windows and have a maximum severity rating of "critical," according to Microsoft's Security Bulletin Advance Notification site. The other patch will affect both Windows and Microsoft Office.