Security Weaknesses in Bluetooth

  • Markus Jakobsson
  • Susanne Wetzel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2020)


We point to three types of potential vulnerabilities in the Bluetooth standard, version 1.0B. The first vulnerability opens up the system to an attack in which an adversary under certain circumstances is able to determine the key exchanged by two victim devices, making eavesdropping and impersonation possible. This can be done either by exhaustively searching all possible PINs (but without interacting with the victim devices), or by mounting a so-called middle-person attack. We show that one part of the key exchange protocol — an exponential back-off method employed in case of incorrect PIN usage — adds no security, but in fact benefits an attacker. The second vulnerability makes possible an attack - which we call a location attack — in which an attacker is able to identify and determine the geographic location of victim devices. This, in turn, can be used for industrial espionage, blackmail, and other undesirable activities. The third vulnerability concerns the cipher. We show two attacks on the cipher, and one attack on the use of the cipher. The former two do not pose any practical threat, but the latter is serious. We conclude by exhibiting a range of methods that can be employed to strengthen the protocol and prevent the newly discovered attacks. Our suggested alterations are simple, and are expected to be possible to be implemented without major modifications.


Application Layer Stream Cipher Location Attack Security Weakness Master Device 
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

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Markus Jakobsson
    • 1
  • Susanne Wetzel
    • 1
  1. 1.Lucent Technologies - Bell LabsInformation Sciences Research CenterMurray HillUSA

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