{"schemaVersion":3,"id":"CVE-2023-32323","aliases":["GHSA-f3wc-3vxv-xmvr","PYSEC-2023-67","UBUNTU-CVE-2023-32323","DEBIAN-CVE-2023-32323"],"status":"published","duplicateOf":null,"title":null,"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.","dates":{"published":"2023-05-26T13:32:01.632Z","modified":"2025-02-13T16:50:32.310Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":5,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"OSV · Pypi","score":5.3,"severity":"medium","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L","exploitability":null,"impact":null,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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