{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "8.0.0"
              },
              {
                "fixed": "8.17.6"
              },
              {
                "introduced": "8.18.0"
              },
              {
                "fixed": "8.18.1"
              },
              {
                "introduced": "9.0.0"
              },
              {
                "fixed": "9.0.1"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "737f0617b0f41a50b735f2e59fd6dca67519c414"
            },
            {
              "fixed": "03939becb3a1a37debf605569aebea0dff9bb2f3"
            },
            {
              "introduced": "9e3be9602a620af998d9bfdbbb632e06ad082c82"
            },
            {
              "fixed": "4f9dfc74ddac310aefb1db8f0766cf47127de3d4"
            },
            {
              "introduced": "f15ae9fbb067e491795deeed285d44c784f997da"
            },
            {
              "fixed": "4e850d791be668438b0d19f729fa734d4bc7657b"
            }
          ],
          "repo": "https://github.com/elastic/logstash",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "elastic",
    "cwe_ids": [
      "CWE-295"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37730.json"
  },
  "details": "Improper certificate validation in Logstash's TCP output could lead to a man-in-the-middle (MitM) attack in “client” mode, as hostname verification in TCP output was not being performed when the ssl_verification_mode =\u003e full was set.",
  "id": "CVE-2025-37730",
  "modified": "2026-08-12T03:51:13.883069056Z",
  "published": "2025-05-06T17:29:07.189Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://discuss.elastic.co/t/logstash-8-17-6-8-18-1-and-9-0-1-security-update-esa-2025-08/377869"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37730.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37730"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/elastic/logstash"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Logstash Improper Certificate Validation in TCP output"
}