Adobe has released updated versions of Adobe Reader and Adobe Acrobat that fix critical security issues that affect Windows and Macintosh systems. These critical security issues could cause the application to crash and potentially allow an attacker to take control of the affected system.
Three different versions of the updates are available dependent upon the currently installed version of Acrobat or Reader installed. These updated versions are Acrobat and Reader XI (11.0.2), X (10.1.6) or Acrobat and Reader 9.5.4.
Note that Adobe has updates available for Reader for Linux, for users who have that product.
More information, as well as links to software updates from Adobe, is available here: