CVE-2023-32323CWE-20

Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites

Medium · published May 26, 2023

CVSS v3.1
5.0
EPSS
1%
Percentile
61.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.0 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00981 · 61.9th percentile
Weakness
CWE-20 · Improper Input Validation
Published
2023-05-26T13:32Z
EPSS history
Timeline
  • 26 MAY 13:32Z
    Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites
    cvelistv5