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.
Published:May 28, 2026
Last Modified:Jun 3, 2026
EPS:May 28, 2026
EPSS Score:0.00014
CVSS Score:5.5
Affected Products
Vendor
Product
Action
Vendor
Element
Product
Synapse
Element
Synapse
Vendor
Element-hq
Product
Synapse
Element-hq
Synapse
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
