Synapse CPU starvation (Denial of Service)_CVE-2026-45078

6.8 / 10

MEDIUM

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

Description

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.

Basic Information

ID CVE-2026-45078

Source GitHub_M

Published May 28, 2026 at 15:52

Affected Product

Vendor element-hq

Product synapse

Version < 1.152.1

Affected Versions element-hq synapse < 1.152.1

CWE Classification

CWE-770

References

github.com /element-hq/synapse/security/advisories/GHSA-8q93-326v-3m7g

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    "published": "2026-05-28T15:52:04.765Z",
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