UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

ClaimChain: Improving the security and privacy of in-band key distribution for messaging

Kulynych, B; Lueks, W; Isaakidis, M; Danezis, G; Troncoso, C; (2018) ClaimChain: Improving the security and privacy of in-band key distribution for messaging. In: Proceeding of Workshop on Privacy in the Electronic Society 2018 (WPES'18). (pp. pp. 86-103). ACM: Toronto, Canada. Green open access

[img]
Preview
Text
1707.06279.pdf - Accepted version

Download (4MB) | Preview

Abstract

The social demand for email end-to-end encryption is barely supported bymainstream service providers. Autocryptisa new community-driven open specification for e-mail encryption that attempts to respond to this demand. In Autocrypt the encryption keys are attached directly to messages, and thus the encryption can be implemented by email clients without any collaboration of the providers. The decentralized nature of this in-band key distribution, however, makes it prone to man-in-the-middle attacks and can leak the social graph of users. To address this problem we introduce ClaimChain, a cryptographic construction for privacy-preserving authentication of public keys. Users store claims about their identities and keys, as well as their beliefs about others, in ClaimChains. These chains form authenticated decentralized repositories that enable users to prove the authenticity of both their keys and the keys of their contacts. ClaimChains are encrypted, and therefore protect the stored information, such as keys and contact identities, from prying eyes. At the same time, ClaimChain implements mechanisms to provide strong non-equivocation properties, discouraging malicious actors from distributing conflicting or inauthentic claims. We implemented ClaimChain and we show that it offers reasonable performance, low overhead, and authenticity guarantees.

Type: Proceedings paper
Title: ClaimChain: Improving the security and privacy of in-band key distribution for messaging
Event: Workshop on Privacy in the Electronic Society 2018 (WPES'18)
ISBN-13: 9781450359894
Open access status: An open access version is available from UCL Discovery
DOI: 10.1145/3267323.3268947
Publisher version: https://doi.org/10.1145/3267323.3268947
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Computer Science
URI: https://discovery.ucl.ac.uk/id/eprint/10068168
Downloads since deposit
17Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item