Denial of service via IXFR queries_CVE-2026-40209

5.3 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Description

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.

Basic Information

ID CVE-2026-40209

Source OX

Published Jun 25, 2026 at 12:23

Modified Jun 25, 2026 at 13:56

Affected Product

Vendor PowerDNS

Product DNSdist

Version 1.9.0

Affected Versions PowerDNS DNSdist 1.9.0
PowerDNS DNSdist 2.0.0

CWE Classification

CWE-772

References

www.dnsdist.org /security-advisories/powerdns-advisory-for-dnsdist-2026-09.html

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    "published": "2026-06-25T12:23:05.694Z",
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