CVE-2025-30355 (GCVE-0-2025-30355)

Vulnerability from cvelistv5 – Published: 2025-03-27 00:59 – Updated: 2025-03-27 13:47
VLAI
Title
Synapse vulnerable to federation denial of service via malformed events
Summary
Synapse is an open source Matrix homeserver implementation. A malicious server can craft events which, when received, prevent Synapse version up to 1.127.0 from federating with other servers. The vulnerability has been exploited in the wild and has been fixed in Synapse v1.127.1. No known workarounds are available.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-03-27 13:47 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7846 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
element-hq synapse Affected: < 1.127.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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