VULNERABILITY INTELLIGENCE
CVE-2023-32323
CVSS score5 MEDIUM
EPSS probability0.98%
CISA KEVNot currently listed
Published2023-05-26
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L
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.
Weakness classification
- security-advisories@github.com: CWE-20
- nvd@nist.gov: CWE-20
Primary references
- security-advisories@github.com — Exploit, Issue Tracking
- security-advisories@github.com — Patch
- security-advisories@github.com — Mitigation, Vendor Advisory
- security-advisories@github.com
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Issue Tracking
- af854a3a-2127-422b-91ae-364da2661108 — Patch
- af854a3a-2127-422b-91ae-364da2661108 — Mitigation, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108