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Paper: The Misuse of RC4 in Microsoft Word and Excel

Authors:
Hongjun Wu
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URL: http://eprint.iacr.org/2005/007
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Abstract: In this report, we point out a serious security flaw in Microsoft Word and Excel. The stream cipher RC4 with key length up to 128 bits is used in Microsoft Word and Excel to protect the documents. But when an encrypted document gets modified and saved, the initialization vector remains the same and thus the same keystream generated from RC4 is applied to encrypt the different versions of that document. The consequence is disastrous since a lot of information of the document could be recovered easily.
BibTeX
@misc{eprint-2005-12346,
  title={The Misuse of RC4 in Microsoft Word and Excel},
  booktitle={IACR Eprint archive},
  keywords={applications / Microsoft Word, Excel, Encryption, RC4, Initialization Vector},
  url={http://eprint.iacr.org/2005/007},
  note={ hongjun@i2r.a-star.edu.sg 12793 received 10 Jan 2005},
  author={Hongjun Wu},
  year=2005
}