CVE-2025-30355
CVSS v3
7.5
HIGH
EPSS Score
7.5 %
exploit probability
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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.
Technical details
- Published
- 2025-03-27
Frequently asked questions
What is CVE-2025-30355?
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.
Is CVE-2025-30355 actively exploited?
Active exploitation of CVE-2025-30355 has not been confirmed. The EPSS score is 7.5%, indicating the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2025-30355?
CVE-2025-30355 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2025-30355 affecting your environment?
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