Authors: Yikai Wang, Xuepei Zhang, Shufan Wu and Yan Cheng
DFRWS EU 2026
Abstract
The widespread adoption of end-to-end encrypted messaging platforms presents significant challenges for digital forensic investigations. This paper presents the first comprehensive forensic analysis of Synapse, the official Matrix Homeserver implementation, focusing on server-side artifacts persisting in both database structures and system logs despite end-to-end encryption. Through systematic examination of production deployments, we identify recoverable digital evidence across 175 database tables and structured log entries, including authentication records, communication timelines, device fingerprints, and file transfer metadata. While message content remains cryptographically protected, our analysis demonstrates substantial investigative value in metadata accessible to investigators with lawful server access. We developed SynExtract, a specialized tool that automates extraction and correlation of artifacts from both Synapse databases and log files. Our findings provide practical guidance and tool for law enforcement personnel conducting forensic examinations of Matrix infrastructure in criminal investigations.