[Resource Topic] 2022/1139: Formal Security Definition of Metadata-Private Messaging

Resource Cryptographic protocols
#1

Welcome to the resource topic for 2022/1139

Title:
Formal Security Definition of Metadata-Private Messaging

Authors: Shengtong Zhang, Arvid Lunnemark, Sualeh Asif

Abstract:

We present a novel, complete definition of metadata-private messaging (MPM) and show that our definition is achievable and non-trivially more general than previous attempts that we are aware of. Our main contributions are:

  1. We describe a vulnerability in existing MPM implementations through a variation of the compromised-friend (CF) attack proposed by Angel et al. Our attack can compromise the exact metadata of any conversations between honest users.

  2. We present a security definition for MPM systems assuming that some friends may be compromised.

  3. We present a protocol satisfying our security definition based on Anysphere, an MPM system we deployed in practice.

ePrint: https://eprint.iacr.org/2022/1139

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .