# CVE-2023-45129: matrix-synapse: Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation

CVE-2023-45129 is fixed in matrix-synapse on 1 platform by DEBIAN-CVE-2023-45129 (version 1.94.0-1), released October 10, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-45129
- Priority: Routine
- CVSS: 4.9 (medium)
- EPSS: 0.0139
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 10, 2023

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | matrix-synapse Debian 14 | 1.94.0-1 | [DEBIAN-CVE-2023-45129](https://patchblox.com/security/data/fix/linux/debian-cve-2023-45129.md) | Oct 10, 2023 |

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