Security Analysis of Mobile Phones Used as OTP Generators

  • Håvard Raddum
  • Lars Hopland Nestås
  • Kjell Jørgen Hole
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6033)


The Norwegian company Encap has developed protocols enabling individuals to use their mobile phones as one-time password (OTP) generators. An initial analysis of the protocols reveals minor security flaws. System-level testing of an online bank utilizing Encap’s solution then shows that several attacks allow a malicious individual to turn his own mobile phone into an OTP generator for another individual’s bank account. Some of the suggested countermeasures to thwart the attacks are already incorporated in an updated version of the online banking system.


Mobile Phone Authentication Protocol Activation Protocol Online Bank Secure Object 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© IFIP International Federation for Information Processing 2010

Authors and Affiliations

  • Håvard Raddum
    • 1
  • Lars Hopland Nestås
    • 1
  • Kjell Jørgen Hole
    • 1
  1. 1.Department of InformaticsUniversity of BergenNorway

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