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.

CVSS v3 2.7 LOW

2.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/element-hq/synapse/security/advisories/GHSA-6qf2-7x63-mm6v	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:element:synapse:*:*:*:*:*:*:*:*

History

04 Jun 2026, 18:04

Type	Values Removed	Values Added
CPE		cpe:2.3:a:element:synapse::::::::
References	~~() https://github.com/element-hq/synapse/security/advisories/GHSA-6qf2-7x63-mm6v -~~	() https://github.com/element-hq/synapse/security/advisories/GHSA-6qf2-7x63-mm6v - Vendor Advisory
First Time		Element synapse Element
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 2.7

28 May 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-28 17:16

Updated : 2026-06-04 18:04

NVD link : CVE-2026-45076

Mitre link : CVE-2026-45076

CVE.ORG link : CVE-2026-45076

JSON object : View

Products Affected

element

synapse

CWE

CWE-20

Improper Input Validation

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