CVE-2023-32323

published 2023-05-26

CVE-2023-32323: 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…

Priority P4 25 medium 4.3 CVSS 3.1

AV N AC L PR L UI N S U C N I N A L

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
debian	matrix-synapse	< matrix-synapse 1.74.0-1 (forky)	matrix-synapse 1.74.0-1 (forky)
matrix-org	synapse	< 1.74.0	1.74.0
matrix	synapse	< 1.74.0	1.74.0

CVSS provenance

nvd v3.1 4.3 MEDIUM CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

osv 4.3 MEDIUM

vendor_debian 5.0 MEDIUM

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CWE-20