PDF problems, again

In the last 20 years PDF (portable document format) files have become a standard for data interchange. Adobe Acrobat or Reader are the common programs that are used to open these files. When they are opened, mysterious contents can include bad stuff (malware).

Since 2001 PDF malware has been regularly released. Because the stuff that goes inside a file can be written in lots of different formats that can be obfuscated, just looking at the file by hand or with an anti-virus program isn’t very effective. Here’s a tip for helping to immunize your machine against these concealed files within these files.

In Acrobat edit/preferences select Trust Manager, then uncheck Allow Opening non PDF…

Thanks to the SANS Internet Storm Center for this tip. More info is at the Internet Storm Center.

This hardening should not break many legit PDF files. If it does, you can cautiously check the box that you just unchecked.