{
  "cveId": "CVE-2023-43796",
  "url": "https://patchblox.com/security/cve/CVE-2023-43796",
  "summary": "CVE-2023-43796 is fixed in matrix-synapse on 1 platform, first by matrix-synapse 0.24.0\u002Bdfsg-1ubuntu0.1~esm4, released October 31, 2023. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "matrix-synapse: Synapse is an open-source Matrix homeserver Prior to versions 1.95.1 and 1.96.0rc1, cached device information of remo...",
  "description": "Synapse is an open-source Matrix homeserver Prior to versions 1.95.1 and 1.96.0rc1, cached device information of remote users can be queried from Synapse. This can be used to enumerate the remote users known to a homeserver. System administrators are encouraged to upgrade to Synapse 1.95.1 or 1.96.0rc1 to receive a patch. As a workaround, the \u0060federation_domain_whitelist\u0060 can be used to limit federation traffic with a homeserver.",
  "published": "2023-10-31T10:15:00Z",
  "severity": "medium",
  "cvss": 5.3,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
  "epss": 0.01196,
  "epssPercentile": 0.68278,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "matrix-synapse",
      "release": "Debian 14",
      "fixedVersion": "1.95.1-1",
      "fix": "DEBIAN-CVE-2023-43796",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2023-43796",
      "released": "2023-10-31T17:15:23Z"
    },
    {
      "platform": "linux",
      "product": "matrix-synapse",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "0.24.0\u002Bdfsg-1ubuntu0.1~esm4",
      "fix": "matrix-synapse 0.24.0\u002Bdfsg-1ubuntu0.1~esm4",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-matrix-synapse-0.24.0-dfsg-1ubuntu0.1-esm4",
      "released": "2023-10-31T10:15:00Z"
    },
    {
      "platform": "linux",
      "product": "matrix-synapse",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1.11.0-1ubuntu0.1~esm2",
      "fix": "matrix-synapse 1.11.0-1ubuntu0.1~esm2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-matrix-synapse-1.11.0-1ubuntu0.1-esm2",
      "released": "2023-10-31T10:15:00Z"
    },
    {
      "platform": "linux",
      "product": "matrix-synapse",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "1.53.0-1ubuntu0.1~esm2",
      "fix": "matrix-synapse 1.53.0-1ubuntu0.1~esm2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-matrix-synapse-1.53.0-1ubuntu0.1-esm2",
      "released": "2024-12-03T09:15:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}