{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "1.9.0"
              },
              {
                "fixed": "1.9.15"
              },
              {
                "introduced": "2.0.0"
              },
              {
                "fixed": "2.0.7"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "298a9d67fb760a12eabe89164f92fb814572aea8"
            },
            {
              "fixed": "3348a4f5e1ea95ed90ad6bbdf9c7f12be72e9bfc"
            },
            {
              "introduced": "89747e81bc60d7950276d5fda3ca669fa81b7cf9"
            },
            {
              "fixed": "5bd46a775a7d72376c6a22b2313173a187d439dd"
            }
          ],
          "repo": "https://github.com/powerdns/pdns",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "OX",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40209.json"
  },
  "details": "An attacker might be able to cause outgoing TCP connections to backend to be stuck until a timeout occurs instead of being released immediately, by sending IXFR queries. This could be used to cause a denial of service if there is a limit to the number of concurrent connections to this backend, or if the process runs out of file descriptors.",
  "id": "CVE-2026-40209",
  "modified": "2026-07-08T05:35:51.766027125Z",
  "published": "2026-06-25T12:23:05.694Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://repo.powerdns.com/"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40209.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40209"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/PowerDNS/pdns"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Denial of service via IXFR queries"
}