CVE-2023-45129
matrix-synapse vulnerable to denial of service due to malicious server ACL events
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.
How to fix CVE-2023-45129
To remediate CVE-2023-45129, upgrade the affected package to a fixed version below.
- —upgrade to 1.94.0-1 or later
- —upgrade to 1.94.0 or later
- —upgrade to 1.94.0 or later
Is CVE-2023-45129 being exploited?
Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 1.94.0-1
- from 0, < 1.94.0
- from 0, < 1.94.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM4.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H |