Telecommunication Systems

, Volume 52, Issue 2, pp 1101–1111 | Cite as

PadSteg: introducing inter-protocol steganography

  • Bartosz Jankowski
  • Wojciech Mazurczyk
  • Krzysztof Szczypiorski
Open Access


Hiding information in network traffic may lead to leakage of confidential information. In this paper we introduce a new steganographic system: the PadSteg (Padding Steganography). To authors’ best knowledge it is the first information hiding solution which represents inter-protocol steganography i.e. usage of relation between two or more protocols from the TCP/IP stack to enable secret communication. PadSteg utilizes ARP and TCP protocols together with an Etherleak vulnerability (improper Ethernet frame padding) to facilitate secret communication for hidden groups in LANs (Local Area Networks). Basing on real network traces we confirm that PadSteg is feasible in today’s networks and we estimate what steganographic bandwidth is achievable while limiting the chance of disclosure. We also point at possible countermeasures against PadSteg.


Steganography ARP Frame padding Etherleak 


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Copyright information

© The Author(s) 2011

Authors and Affiliations

  • Bartosz Jankowski
    • 1
  • Wojciech Mazurczyk
    • 1
  • Krzysztof Szczypiorski
    • 1
  1. 1.Institute of TelecommunicationsWarsaw University of TechnologyWarsawPoland

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