Attribute-Based Authentication in Secure Group Messaging for Distributed Environments and Safer Online Spaces

Computer Science > Cryptography and Security [Submitted on 20 May 2024 (v1), last revised 22 Apr 2026 (this version, v3)] Attribute-Based Authentication in Secure Group Messaging for Distributed Environments and Safer Online Spaces David Soler (1), Carlos Dafonte (1), Manuel Fernández-Veiga (2), Ana Fernández Vilas (2), Francisco J. Nóvoa (1) ((1) CITIC, Universidade da Coruňa, A Coruňa, Spain, (2) atlanTTic, Universidade de Vigo, Vigo, Spain) The Messaging Layer security (MLS) and its underlying Continuous Group Key Agreement (CGKA) protocol allows a group of users to share a cryptographic secret in a dynamic manner, such that the secret is modified in member insertions and deletions. Although this flexibility makes MLS ideal for implementations in distributed environments, a number of issues need to be overcome. Particularly, the use of digital certificates for authentication in a group goes against the group members' privacy. In this work we provide an alternative method of authentication in which the solicitors, instead of revealing their identity, only need to prove possession of certain attributes, dynamically defined by the group, to become a member. Instead of digital certificates, we employ Attribute-Based Credentials accompanied with Selective Disclosure in order to reveal the minimum required amount of information and to prevent attackers from linking the activity of a user through multiple groups. We formally define a CGKA variant named Attribute-Authenticated Continuous Group Key Agreement (AA-CGKA) and provide security proofs for its properties of Requirement Integrity, Unforgeability and Unlinkability. We also provide an implementation of our AA-CGKA scheme and show that it achieves performance similar to a trivial certificate-based solution. Comments: 35 pages, 9 figures. Published in Computer Networks Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2405.12042 [cs.CR]   (or arXiv:2405.12042v3 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2405.12042 Focus to learn more Related DOI: https://doi.org/10.1016/j.comnet.2026.112302 Focus to learn more Submission history From: David Soler [view email] [v1] Mon, 20 May 2024 14:09:28 UTC (502 KB) [v2] Fri, 30 May 2025 10:25:00 UTC (319 KB) [v3] Wed, 22 Apr 2026 11:37:42 UTC (300 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2024-05 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)