The default configuration of Adobe Reader and Acrobat 9.x before 9.3, and 8.x before 8.2 on Windows and Mac OS X, does not enable the Enhanced Security feature, which has unspecified impact and attack vectors, related to a "script injection vulnerability," as demonstrated by Acrobat Forms Data Format (FDF) behavior that allows cross-site scripting (XSS) by user-assisted remote attackers.