CVE-2023-32323
Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites
- State
- Published
- Severity
- 5.0 Medium
- Published
- May 26, 2023
- Updated
- Feb 13, 2025
- Reserved
- May 8, 2023
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 5.0 Medium | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L | GitHub_M |
Weaknesses
- CWE-20 Improper Input Validation
Affected Products
| Product | Versions |
|---|---|
synapsematrix-org |
|
References
- https://github.com/matrix-org/synapse/security/advisories/GHSA-f3wc-3vxv-xmvr
- https://github.com/matrix-org/synapse/issues/14492
- https://github.com/matrix-org/synapse/pull/14642
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UJIJRP5ZH6B3KGFLHCAKR2IX2Y4Z25QD/
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