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.