New Steganographic Techniques for the OOXML File Format
The simplest container of digital information is the file and among the vast array of files currently available, MS-Office files are the most widely used. The “Microsoft Compound Document File Format” (MCDFF) has often been used to host secret information. The new format created by Microsoft, first used with MS-Office 2007, makes use of a new standard, the “Office Open XML Formats” (OOXML). The benefits include that the new format introduces the OOXML format, which lowers the risk of information leakage, as well as the use of MS-Office files as containers for steganography.
This work presents some new methods of embedding information into the OOXML file format which can be extremely useful when using MS-Office documents in steganography. The authors highlight how the new methods introduced in this paper can also be used in many other scenarios, not only in MS-Office documents. An evaluation of the limits of the proposed methods is carried out by comparing them against the tool introduced by Microsoft to sanitize MS-Office files. The methods presented can be combined in order to extend the amount of data to be hidden in a single cover file.
KeywordsSteganography OOXML Format Stegosystem Document Steganography Microsoft Office Document Information Hiding Document Metadata Covert Channel
- 2.Deutsch, P.: DEFLATE Compressed Data Format Specification version 1.3 (May 1996), http://www.ietf.org/rfc/rfc1951.txt
- 3.ECMA International: Final draft standard ECMA-376 Office Open XML File Formats - Part 1. In: ECMA International Publication (December 2008)Google Scholar
- 4.Erika Ehrli, M.C.: Building server-side document generation solutions using the open xml object model (August 2007), http://msdn.microsoft.com/en-us/library/bb735940%28office.12%29.aspx
- 5.Frank Rice, M.C.: Microsoft MSDN. Introducing the Office (2007) Open XML File Formats (May 2006), http://msdn.microsoft.com/it-it/library/aa338205.aspx
- 7.Hao-ran, Z., Liu-sheng, H., Yun, Y., Peng, M.: A new steganography method via combination in powerpoint files. In: 2010 International Conference on Computer Application and System Modeling (ICCASM), vol. 2, pp. V2-62–V2-66 (October 2010)Google Scholar
- 8.Jing, M.Q., Yang, W.C., Chen, L.H.: A new steganography method via various animation timing effects in powerpoint files. In: 2009 International Conference on Machine Learning and Cybernetics, vol. 5, pp. 2840–2845 (July 2009)Google Scholar
- 9.Lin, I.C., Hsu, P.K.: A data hiding scheme on word documents using multiple-base notation system. In: 2010 Sixth International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP), pp. 31–33 (October 2010)Google Scholar
- 11.Microsoft Corporation: Compare office professional plus 2010, and the 2007 suite, http://office.microsoft.com/en-us/professional-plus/professional-plus-version-comparison-FX101871482.aspx (visited May 2011)
- 12.Microsoft Corporation: Remove hidden data and personal information from office documents, http://office.microsoft.com/en-us/excel-help/remove-hidden-data-and-personal-information-from-office-documents-HA010037593.aspx (visited May 2011)
- 13.Microsoft Press Release: Microsoft office 2010 now available for consumers worldwide, http://www.microsoft.com/presspass/press/2010/jun10/06-152010officelaunchpr.mspx (visited May 2011)
- 14.MSDN Library: Introduction to macros, http://msdn.microsoft.com/en-us/library/bb220916.aspx (visited May 2011)
- 16.Wikipedia: ZIP (file format), http://en.Wikipedia.org/wiki/ZIP_file_format (visited May 2011)