7.1High
CVE-2025-30355Synapse vulnerable to federation denial of service via malformed events
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.
Weakness (CWE):
CWE-20
Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.
Affected products and versions
| Vendor | Product | Versions | |
|---|---|---|---|
| element-hq | synapse | < 1.127.1 | |
| matrix | synapse | < 1.127.1 |
References and patches
CPE matches (NVD) (1)
cpe:2.3:a:matrix:synapse:*:*:*:*:*:*:*:*< 1.127.1