CVSS 3.1
4.3 mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:LCVE-2023-32323
Medium (4.3) in matrix synapse. EPSS 1.0% chance of exploitation in the next 30 days. Fixed in matrix-synapse 1.74.0.
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. A malicious user on a Synapse homeserver X with permission to create certain state events can disable outbound federation from X to an arbitrary homeserver Y. Synapse instances with federation disabled are not affected. In versions of Synapse up to and including 1.73, Synapse did not limit the size of `invite_room_state`, meaning that it was possible to create an arbitrarily large invite event. Synapse 1.74 refuses to create oversized `invite_room_state` fields. Server operators should upgrade to Synapse 1.74 or newer urgently.
Severity
- EPSS
- 1.0% chance of exploitation in the next 30 days; higher than 62% of CVEs (scores of 2026-10-31)
- CWE
- CWE-20
- Published
- Modified
- Record from
- the NVD, synced
Affected
- matrix:synapse
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-f3wc-3vxv-xmvr | PyPI | matrix-synapse | <1.74.0 | 1.74.0 |
| PYSEC-2023-67 | PyPI | matrix-synapse | <1.74.0 | 1.74.0 |
References
- https://github.com/matrix-org/synapse/issues/14492
- https://github.com/matrix-org/synapse/pull/14642
- https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/
- https://github.com/matrix-org/synapse/issues/14492