{
  "cveId": "CVE-2025-30355",
  "url": "https://patchblox.com/security/cve/CVE-2025-30355",
  "summary": "CVE-2025-30355 is fixed in matrix-synapse on 1 platform by DEBIAN-CVE-2025-30355 (version 1.121.0-6), released March 27, 2025. It is not reported as exploited. Patch Radar priority: High.",
  "title": "matrix-synapse: Synapse is an open source Matrix homeserver implementation",
  "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.",
  "published": "2025-03-27T01:15:12Z",
  "severity": "high",
  "cvss": 7.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.01226,
  "epssPercentile": 0.69002,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "matrix-synapse",
      "release": "Debian 14",
      "fixedVersion": "1.121.0-6",
      "fix": "DEBIAN-CVE-2025-30355",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2025-30355",
      "released": "2025-03-27T01:15:12Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}