Adobe have releases security updates for Adobe Reader and Acrobat. This patch is for the same vulnerability that affected Adobe Flash as detailed in Post 786903
You can either use the built in "Check for updates" feature of Reader/Acrobat, or download the patches from the following links:
Adobe Reader 9.1.3 update (Windows)
Adobe Acrobat 9.1.3 Professional and Standard Update (Windows)

There are also updates for Mac and Linux users, which can be downloaded from