CVE-2026-45078

Synapse is an open source Matrix homeserver implementation. Prior to 1.152.1, local authenticated users can cause Synapse to starve other requests of CPU and lead to other requests failing, causing other users to be denied service. This vulnerability is fixed in 1.152.1.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/element-hq/synapse/security/advisories/GHSA-8q93-326v-3m7g	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

03 Jun 2026, 02:15

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
References	~~() https://github.com/element-hq/synapse/security/advisories/GHSA-8q93-326v-3m7g -~~	() https://github.com/element-hq/synapse/security/advisories/GHSA-8q93-326v-3m7g - Mitigation, Vendor Advisory
CPE		cpe:2.3:a:element:synapse::::::::
First Time		Element synapse Element

28 May 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-28 17:16

Updated : 2026-06-03 02:15

NVD link : CVE-2026-45078

Mitre link : CVE-2026-45078

CVE.ORG link : CVE-2026-45078

JSON object : View

Products Affected

element

synapse

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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