CVE-2026-45076
Synapse pagination Denial of Service
2.7
LOW
CVSS 3.1
EPSS 0.09%
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.
How to fix CVE-2026-45076
To remediate CVE-2026-45076, upgrade the affected package to a fixed version below.
- —upgrade to 1.152.1-1 or later
- —upgrade to 1.152.1 or later
- —upgrade to 1.152.1 or later
Is CVE-2026-45076 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 1.152.1-1
- from 0, < 1.152.1
- from 0, < 1.152.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | LOW2.7 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L |