CVE-2026-45076

Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, in federated rooms, malicious homeservers can craft room events in such a way that prevents Synapse from providing full history to paginating clients. Clients could therefore fail to display room history. This vulnerability is fixed in 1.152.1.

More information : https://github.com/element-hq/synapse/security/advisories/GHSA-6qf2-7×63-mm6v