Microsoft has only released one patch for its first update of 2010.

As confirmed last week, one bulletin that addresses a single vulnerability in Windows is being released this month. Microsoft has said that the vulnerability is critical on Windows 2000 and low for all other platforms.

Tom Kelchner, research office manager at Sunbelt Software, said: “The single patch will come as a relief to recession-shrunken IT staffs that have had to deal with numerous fixes for the past few months, including the mammoth Tuesday release in October when they faced 13 security bulletins.”

Shavlik said that it is not uncommon for Microsoft to have a light patch month in January. A year ago only one bulletin was released, with two released in January 2007 and 2008.

Jason Miller, security and data team manager at Shavlik Technologies, said: “The security bulletin for this month is rated as critical and affects all supported operating systems, including Windows 7 and Windows 2008 R2. The bulletin has drastic swings in severity ratings. Windows 2000 SP4 has a rating of critical, with the rest of the operating systems rated as low.”