This week, a buffer overflow vulnerability has been discovered in Adobe Reader 5.0.10. For Linux users, the only fix is an upgrade to version 7.

Unfortunately, Adobe Reader 7 can execute Javascript inside PDF documents, which is used by some authors to track readers. Javascript can be disabled with the menu item Edit - Preferences - JavaScript, but everytime you exit Acrobat Reader, it will ask you to reenable Javascript. To get rid of this annoying warning, do the following:

cd ~/.adobe/Acrobat/7.0/JavaScripts
rm glob.settings.js
ln -s /dev/null glob.settings.js

Update 11 Jul 2005: After upgrading from Adobe Reader 5 to 7, you also need to change your Mozilla or Firefox configuration. Instructions for Fedora Core can be found in the Fedora Core 4 Linux Installation Notes.