{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "8.0.0"
              },
              {
                "last_affected": "8.9.2"
              },
              {
                "introduced": "8.0.0"
              },
              {
                "last_affected": "8.9.2"
              },
              {
                "introduced": "8.0.0"
              },
              {
                "last_affected": "8.9.2"
              },
              {
                "introduced": "8.0.0"
              },
              {
                "last_affected": "8.9.2"
              }
            ]
          },
          "events": [
            {
              "introduced": "6afb387ae002e5a8dc2427b53225aa42681e4208"
            },
            {
              "last_affected": "3620fff841a6ee8a11d8e4f1661fff1ea5d5e1c3"
            },
            {
              "introduced": "6afb387ae002e5a8dc2427b53225aa42681e4208"
            },
            {
              "last_affected": "3620fff841a6ee8a11d8e4f1661fff1ea5d5e1c3"
            },
            {
              "introduced": "6afb387ae002e5a8dc2427b53225aa42681e4208"
            },
            {
              "last_affected": "3620fff841a6ee8a11d8e4f1661fff1ea5d5e1c3"
            },
            {
              "introduced": "6afb387ae002e5a8dc2427b53225aa42681e4208"
            },
            {
              "last_affected": "3620fff841a6ee8a11d8e4f1661fff1ea5d5e1c3"
            }
          ],
          "repo": "https://github.com/elastic/apm-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "details": "It was discovered that when acting as TLS clients, Beats, Elastic Agent, APM Server, and Fleet Server did not verify whether the server certificate is valid for the target IP address; however, certificate signature validation is still performed. More specifically, when the client is configured to connect to an IP address (instead of a hostname) it does not validate the server certificate's IP SAN values against that IP address and certificate validation fails, and therefore the connection is not blocked as expected.",
  "id": "CVE-2023-31421",
  "modified": "2026-03-13T21:54:33.465185682Z",
  "published": "2023-10-26T04:15:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://discuss.elastic.co/t/beats-elastic-agent-apm-server-and-fleet-server-8-10-1-security-update-improper-certificate-validation-issue-esa-2023-16/343385"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.elastic.co/community/security"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}