Unspecified vulnerability in the PRC component in Adobe Reader and Acrobat 9.x before 9.4.7 on Windows Adobe Reader and Acrobat 9.x through 9.4.6 on Mac OS X Adobe Reader and Acrobat 10.x through 10.1.1 on Windows and Mac OS X and Adobe Reader 9.x through 9.4.6 on UNIX allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via unknown vectors as exploited in the wild in December 2011.