Crafting Web Counters into Covert Channels

  • Xiapu Luo
  • Edmond W. W. Chan
  • Rocky K. C. Chang
Part of the IFIP International Federation for Information Processing book series (IFIPAICT, volume 232)


Almost all the previously proposed network storage channels write covert messages in the packets’ protocol fields. In contrast, we present in this paper a new network storage channel WebShare that uses the plentiful, public Web counters for storage. Therefore, the physical locations of the WebShare encoder and decoder are not restricted to a single path. To make WebShare practical, we have addressed a number of thorny issues, such as the “noise” introduced by other legitimate Web requests, and synchronization between encoder and decoder. For the proof-of-concept purpose, we have experimented a WebShare prototype in the Internet, and have showed that it is practically feasible even when the Web counter and the encoder/decoder are separated by more than 20 router hops.


Covert Channel Covert Communication Spread Spectrum Communication Network Time Protocol Storage Channel 


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Copyright information

© International Federation for Information Processing 2007

Authors and Affiliations

  • Xiapu Luo
    • 1
  • Edmond W. W. Chan
    • 1
  • Rocky K. C. Chang
    • 1
  1. 1.Department of ComputingThe Hong Kong Polytechnic UniversityHong KongChina

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