Also important from an enterprise standpoint is the cumulative update Microsoft issued Tuesday to fix three separate remotely exploitable vulnerabilities in Internet Explorer, Sutton said. Two of the flaws addressed in the bulletin -- both involving DirectAnimation ActiveX controls -- have already been publicly disclosed, and exploit code for them has begun circulating, he said.

November's security update is smaller than others this year in terms of the overall number of patches announced, according to Mark Allen, data manager at Shavlik Technologies LLC. "But the percentage that are critical and remotely exploitable is still pretty high," he noted. Patches for those are definitely worth deploying as quickly as possible, he said.

All of the flaws addressed by the current set of fixes -- except for the one in Workstation Service -- can be exploited over the Internet, though they require users to either go to malicious Web sites or click on malicious e-mails, Allen said.

The Workstation Service flaw, on the other hand, only requires an attacker to send a specially crafted packet to the network to be exploited, he said. "The potential for exploiting this one is pretty high," he added.