CVE-2026-40209
Fixed in a distro release EPSS <1%CVSS 5.3
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.
Products: powerdns dnsdist
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 12 | dnsdist | no fix |
| Debian 13 | dnsdist | 1.9.15-0+deb13u1 |
| Debian 14 | dnsdist | 2.1.0-1 |
| SUSE Linux Enterprise Server 16.0 | dnsdist | 1.9.15-160000.1.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | dnsdist | 1.9.15-160000.1.1 |
| Ubuntu 16.04 LTS | dnsdist | no fix |
| Ubuntu 25.10 | dnsdist | no fix |
| Ubuntu 26.04 LTS | dnsdist | no fix |
| Ubuntu 26.10 | dnsdist | no fix |
| Ubuntu Pro 18.04 LTS | dnsdist | no fix |
| Ubuntu Pro 20.04 LTS | dnsdist | no fix |
| Ubuntu Pro 22.04 LTS | dnsdist | no fix |
| Ubuntu Pro 24.04 LTS | dnsdist | no fix |
| openSUSE Leap 16.0 | dnsdist | 1.9.15-160000.1.1 |
| openSUSE Tumbleweed | dnsdist | 2.0.7-1.1 |