Reducing Metadata Leakage from Encrypted Files and Communication with PURBs

@article{Nikitin2019ReducingML,
  title={Reducing Metadata Leakage from Encrypted Files and Communication with PURBs},
  author={Kirill Nikitin and Ludovic Barman and Matthew Underwood and Bryan Ford},
  journal={Proceedings on Privacy Enhancing Technologies},
  year={2019},
  volume={2019},
  pages={33 - 6}
}
Abstract Most encrypted data formats leak metadata via their plaintext headers, such as format version, encryption schemes used, number of recipients who can decrypt the data, and even the recipients’ identities. This leakage can pose security and privacy risks to users, e.g., by revealing the full membership of a group of collaborators from a single encrypted e-mail, or by enabling an eavesdropper to fingerprint the precise encryption software version and configuration the sender used. We… 

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SoK

  • Harry Halpin
  • Proceedings of the 15th International Conference on Availability, Reliability and Security
  • 2020

SoK: why Johnny can't fix PGP standardization

  • H. Halpin
  • Computer Science, Mathematics
    ARES
  • 2020
The core reason for the inability to "fix" PGP is the lack of a simple AEAD interface which in turn requires a decentralized public key infrastructure to work with email, yet even if standards like MLS replace PGP, the deployment of a decentralized PKI remains an open issue.

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