Last week Redmond-based software giant Microsoft announced that, as part of the Patch Tuesday program (updates are released every second Tuesday of the month), it will release a grand total of 17 security bulletins. All we knew until now was that the aforementioned 17 bulletins addressed a total of 40 vulnerabilities that plague the Windows operating system, the Office productivity suite, the Internet Explorer web browser, Microsoft SharePoint, and Microsoft Exchange.

We also knew that out of the 17 bulletins, one is rated as moderate, fourteen are rated as important, and two are rated as critical. Since December 2010 Patch Tuesday has come and gone, Microsoft has now released additional details about these security bulletins and the vulnerabilities they address.

Normally we go over all the bulletins included in the Patch Tuesday releases. But this time there are just too many of them, so we will focus on the 2 critical bulletins. Here are the details Microsoft made public:

• MS10-090

Title: Cumulative Security Update for Internet Explorer
Rating: Critical
Impact: Remote code execution
Description: Four privately reported vulnerabilities and three publicly disclosed vulnerabilities in Internet Explorer. The most severe vulnerabilities could allow remote code execution if a user views a specially crafted Web page using Internet Explorer.
Most likely attack vector: Victim browses to a malicious webpage.
Affected software: Microsoft Windows, Internet Explorer
- IE 6 Windows XP Service Pack 3
- IE 6 Windows XP Professional x64 Edition Service Pack 2
- IE 6 Windows Server 2003 Service Pack 2
- IE 6 Windows Server 2003 x64 Edition Service Pack 2
- IE 6 Windows Server 2003 with SP2 for Itanium-based Systems
- IE 7 Windows XP Service Pack 3
- IE 7 Windows XP Professional x64 Edition Service Pack 2
- IE 7 Windows Server 2003 Service Pack 2
- IE 7 Windows Server 2003 x64 Edition Service Pack 2
- IE 7 Windows Server 2003 with SP2 for Itanium-based Systems
- IE 7 Windows Vista Service Pack 1 and Windows Vista Service Pack 2
- IE 7 Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2
- IE 7 Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2
- IE 7 Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2
- IE 7 Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2
- IE 8 Windows XP Service Pack 3
- IE 8 Windows XP Professional x64 Edition Service Pack 2
- IE 8 Windows Server 2003 Service Pack 2
- IE 8 Windows Server 2003 x64 Edition Service Pack 2
- IE 8 Windows Vista Service Pack 1 and Windows Vista Service Pack 2
- IE 8 Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2
- IE 8 Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2
- IE 8 Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2
- IE 8 Windows 7 for 32-bit Systems
- IE 8 Windows 7 for x64-based Systems
- IE 8 Windows Server 2008 R2 for x64-based Systems
- IE 8 Windows Server 2008 R2 for Itanium-based Systems

• MS10-091

Title: Vulnerabilities in the OpenType Font (OTF) Driver Could Allow Remote Code Execution
Rating: Critical
Impact: Remote code execution
Description: Several privately reported vulnerabilities in the Windows Open Type Font (OTF) driver that could allow remote code execution. An attacker could host a specially crafted OpenType Font on a network share. The affected control path is then triggered when the user navigates to the share in Windows Explorer, allowing the specially crafted font to take complete control over an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.
Most likely attack vector: Victim using explorer.exe browses to a folder containing a malicious OTF file.
Affected software: Microsoft Windows
- Windows XP Service Pack 3
- Windows XP Professional x64 Edition Service Pack 2
- Windows Server 2003 Service Pack 2
- Windows Server 2003 x64 Edition Service Pack 2
- Windows Server 2003 with SP2 for Itanium-based Systems
-Windows Vista Service Pack 1 and Windows Vista Service Pack 2
- Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2
- Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2*
- Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2
- Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2
- Windows 7 for 32-bit Systems
- Windows 7 for x64-based Systems
- Windows Server 2008 R2 for x64-based Systems
- Windows Server 2008 R2 for Itanium-based Systems

Details on the remaining 15 security bulletins that Microsoft rolled out this Patch Tuesday are available here and here.

The Microsoft Security Response Center (MSRC) has provided this visual representation of the December 2010 Patch Tuesday.