Seven of the flaws were rated "critical" by the company, while the other two were rated "important."

The most dangerous of the vulnerabilities in this month's batch is a flaw in Microsoft's Workstation Service memory, according to security vendor Symantec Corp. The flaw is remotely executable and allows attackers to potentially take complete control of compromised systems to create new user accounts, install programs and view, modify or delete data.

"A successful exploitation of this vulnerability could result in a complete system compromise," Symantec said in its advisory. "This issue can be exploited by remote anonymous attackers on Windows 2000, Windows XP and possibly Windows Server 2003 systems." Symantec added that a wide variety of component technologies and services are affected by this issue.

A remotely exploitable flaw in Microsoft XML Core Services poses another critical threat to enterprises because it has already been publicly disclosed, said Michael Sutton, security evangelist at Web application security firm SPI Dynamics Inc.

As with the Workstation Service flaw, attackers who successfully exploit this vulnerability could take complete administrative control of systems, Microsoft said in its advisory. Enterprises need to make patching this flaw a top priority because public exploits have already started becoming available, Sutton said.