Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. Prior to version 1.94.0, a malicious server ACL event can impact performance temporarily or permanently leading to a persistent denial of service. Homeservers running on a closed federation (which presumably do not need to use server ACLs) are not affected. Server administrators are advised to upgrade to Synapse 1.94.0 or later. As a workaround, rooms with malicious server ACL events can be purged and blocked using the admin API.
Advisories
Source ID Title
EUVD EUVD EUVD-2023-0135 Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. Prior to version 1.94.0, a malicious server ACL event can impact performance temporarily or permanently leading to a persistent denial of service. Homeservers running on a closed federation (which presumably do not need to use server ACLs) are not affected. Server administrators are advised to upgrade to Synapse 1.94.0 or later. As a workaround, rooms with malicious server ACL events can be purged and blocked using the admin API.
Github GHSA Github GHSA GHSA-5chr-wjw5-3gq4 matrix-synapse vulnerable to denial of service due to malicious server ACL events
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 28 May 2025 16:30:00 +0000

Type Values Removed Values Added
References

Thu, 22 May 2025 06:15:00 +0000


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-02-13T17:13:47.801Z

Reserved: 2023-10-04T16:02:46.328Z

Link: CVE-2023-45129

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2023-10-10T18:15:19.093

Modified: 2024-11-21T08:26:24.017

Link: CVE-2023-45129

cve-icon Redhat

Severity : Moderate

Publid Date: 2023-10-10T00:00:00Z

Links: CVE-2023-45129 - Bugzilla

cve-icon OpenCVE Enrichment

No data.