Why MAC Address Randomization is not Enough: An Analysis of Wi-Fi Network Discovery Mechanisms

  title={Why MAC Address Randomization is not Enough: An Analysis of Wi-Fi Network Discovery Mechanisms},
  author={M. Vanhoef and C{\'e}lestin Matte and Mathieu Cunche and Leonardo Sampaio Cardoso and Frank Piessens},
  journal={Proceedings of the 11th ACM on Asia Conference on Computer and Communications Security},
We present several novel techniques to track (unassociated) mobile devices by abusing features of the Wi-Fi standard. [] Key Method We then combine these fingerprints with incremental sequence numbers, to create a tracking algorithm that does not rely on unique identifiers such as MAC addresses. Based on real-world datasets, we demonstrate that our algorithm can correctly track as much as 50% of devices for at least 20 minutes. We also show that commodity Wi-Fi devices use predictable scrambler seeds.

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