CVSS 3.1
4.9 mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:HCVE-2023-45129
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.
Severity
- EPSS
- 1.4% chance of exploitation in the next 30 days; higher than 72% of CVEs (scores of 2026-10-31)
- CWE
- CWE-770
- Published
- Modified
- Record from
- the NVD, synced
Affected
- fedoraproject:fedora
- matrix:synapse
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-5chr-wjw5-3gq4 | PyPI | matrix-synapse | <1.94.0 | 1.94.0 |
| PYSEC-2023-199 | PyPI | matrix-synapse | <1.94.0 | 1.94.0 |
References
- https://github.com/matrix-org/synapse/pull/16360
- https://github.com/matrix-org/synapse/security/advisories/GHSA-5chr-wjw5-3gq4
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/KEVRB4MG5UXQ5RLZHSUJXM5GWEBYYS5B/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/N6P4QULVUE254WI7XF2LWWOGHCYVFXFY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WRO4MPQ6HOXIUZM6RJP6VTCTMV7RD2T3/