Synapse pagination denial of service_CVE-2026-45076

5.1 / 10

MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Description

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.

Basic Information

ID CVE-2026-45076

Source GitHub_M

Published May 28, 2026 at 15:50

Affected Product

Vendor element-hq

Product synapse

Version < 1.152.1

Affected Versions element-hq synapse < 1.152.1

CWE Classification

CWE-20

References

github.com /element-hq/synapse/security/advisories/GHSA-6qf2-7x63-mm6v

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    "published": "2026-05-28T15:50:25.842Z",
    "modified": "2026-05-28T15:50:25.842Z",
    "type": "cve",
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