Adobe Reader 8.x and 9.x on Windows is able to execute EXE files that are embedded in a PDF document, which makes it easier for remote attackers to trick users into executing arbitrary code via a crafted document.
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.