{"id":"CVE-2026-40209","summary":"Denial of service via IXFR queries","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.","modified":"2026-07-08T08:11:24.487085282Z","published":"2026-06-25T12:23:05.694Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40209.json","cna_assigner":"OX"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/powerdns/pdns","events":[{"introduced":"298a9d67fb760a12eabe89164f92fb814572aea8"},{"fixed":"3348a4f5e1ea95ed90ad6bbdf9c7f12be72e9bfc"},{"introduced":"89747e81bc60d7950276d5fda3ca669fa81b7cf9"},{"fixed":"5bd46a775a7d72376c6a22b2313173a187d439dd"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"1.9.0"},{"fixed":"1.9.15"},{"introduced":"2.0.0"},{"fixed":"2.0.7"}]}}],"versions":["dnsdist-1.9.14","dnsdist-2.0.6","dnsdist-2.0.5","dnsdist-2.0.2","dnsdist-2.0.1","dnsdist-1.9.11","dnsdist-2.0.0","dnsdist-1.9.10","dnsdist-1.9.9","dnsdist-1.9.8","dnsdist-1.9.7","dnsdist-1.9.6","dnsdist-1.9.5","dnsdist-1.9.4","dnsdist-1.9.3","dnsdist-1.9.2","dnsdist-1.9.1","dnsdist-1.9.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40209.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}]}