CVE-2023-32323 (GCVE-0-2023-32323)

Vulnerability from cvelistv5 – Published: 2023-05-26 13:32 – Updated: 2025-02-13 16:50
VLAI
Title
Synapse Outgoing federation to specific hosts can be disabled by sending malicious invites
Summary
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.
Severity
5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-01-14 20:00 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
matrix-org synapse Affected: < 1.74.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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