Microsoft has released one new security bulletin for January.  This patch Tuesday also marks the quarterly security bulletin release for Adobe.  The highly publicized exploit for Adobe Acrobat and Reader will be patched today.

Unlike most months, the bulletin administrators should look at first is the Adobe patch when it is released later today.  This bulletin will patch vulnerabilities that are currently in the wild affecting users.  With any zero-day exploit, it is important to address the issue as soon as possible.

Microsoft's bulletin, MS10-001, affects the way the operating system handled Embedded OpenType Fonts.  Because EOT fonts are typical on websites, it is important to patch client systems first.  A vulnerable client system needs to only visit a website containing malicious EOT fonts to allow remote code execution on the machine.

Even though this bulletin affects all operating systems, Windows 2000 is the only operating system with a high severity.  It is rated as "Critical" by Microsoft with the remaining operating systems rated as "Low".  This is because Windows 2000 actively uses the vulnerable code to decompress the EOT files.  The other operating systems do not use this code to do this.  Although, Microsoft is rating this as Low instead of not applicable because it could be theoretically possible to have a third party program use the code on these operating systems.  The likelihood of this scenario is extremely low.  This bulletin addresses one vulnerability that is not publically known at this time.

This may seem like an extremely light month for new Microsoft Security Bulletins, but the past few years has shown us this trend:

  • January 2009 – 1 Security Bulletin
  • January 2008 – 2 Security Bulletins
  • January 2007 – 2 Security Bulletins

Administrators should be prepared for next month if the trends hold true:

  • February 2009 - 4 Security Bulletins
  • February 2008 - 11 Security Bulletins
  • February 2007 - 12 Security Bulletins

- Jason Miller