The vulnerability affects all versions of Adobe Reader and Acrobat 9.x and higher, including Adobe Reader X and Adobe Acrobat X (10.1) for Windows, Macintosh, and UNIX. Adobe has published that they are currently engineering a fix for the issue and expect to make it available on December 12, 2011. The exploit has already been seen active in the wild and it is expected that it’s being used by criminal and espionage organizations to try to infiltrate defense corporations and others.
Source: https://thehackernews.com/2011/12/critical-zero-day-vulnerability-in.html