Users of Adobe Pro \ Reader have an option to disallow opening of any non-pdf file attachments with external applications by doing the following:
In Acrobat Preferences, selecting > Edit > Preferences > Categories > Trust Manager > PDF File Attachments and clearing (unchecking) the box "Allow opening of non-PDF file attachments with external applications"
Sometimes even if you make the above mentioned settings change it will allow some executables to be launched from pdf. In order to work around this problem set the following registry entries that block 100% of any executable launching from PDF
- Set HKCU\Software\Adobe\Acrobat Reader\<version>\Originals\bAllowOpenFile (DWORD) to 0
- HKCU\Software\Adobe\Acrobat Reader\<version>\Originals\bSecureOpenFile (DWORD) to 1