The company's December Security Bulletin Advance Notification does not provide any additional details about the two issues that will be patched this coming Tuesday.
The critical patch is expected to address an exploitable flaw in Internet Explorer (IE).
Microsoft issued a security advisory soon thereafter to inform end users about the issue.
November's patch Tuesday also included a patch that Microsoft had labeled "critical" as well. That patch fixed a flaw in the Windows rendering engine.
This article was first published on InternetNews.com.