Hidden Data and Metadata in Adobe PDF Files: Publication Risks and Countermeasures Enterprise Applications Division of the Systems and Network Analysis Center (SNAC) Information Assurance Directorate

The Portable Document Formal is pervasive and is used for publishing documents on the web, exchanging files between government entities and government contractors, and for interactive content such as forms and multimedia. Some of the reasons for its popularity include the wide availability of PDF authoring told and freely available readers, cross-platform interoperability, and the ability to maintain the appearance of content across clients with varying hardware and software.