Description
A client might theoretically be able to cause a mismatch between queries sent to a backend and the received responses by sending a flood of perfectly timed queries that are routed to a TCP-only or DNS over TLS backend.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| PowerDNS | DNSdist | 1.9.0 – < 1.9.13, 2.0.0 – < 2.0.4 | 1.9.13 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | dnsdist | 2.0.4-1 | — |
| Debian 13 | dnsdist | 1.9.14-0+deb13u1 | — |
| Debian 12 | dnsdist | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | dnsdist | No fix yet | — |
| Ubuntu 26.04 LTS | dnsdist | No fix yet | — |
| Ubuntu 25.10 | dnsdist | No fix yet | — |
| Ubuntu 16.04 LTS | dnsdist | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | dnsdist | No fix yet | — |
| Ubuntu Pro 22.04 LTS | dnsdist | No fix yet | — |
| Ubuntu Pro 20.04 LTS | dnsdist | No fix yet | — |
| Ubuntu Pro 18.04 LTS | dnsdist | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | dnsdist | 1.9.13-160000.1.1 | SUSE-SU-2026:22319-1 |
| SLES 16.0 | dnsdist | 1.9.13-160000.1.1 | SUSE-SU-2026:22319-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | dnsdist | 2.0.5-1.1 | openSUSE-SU-2026:10632-1 |
| openSUSE Leap 16.0 | dnsdist | 1.9.13-160000.1.1 | openSUSE-SU-2026:21015-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dnsdist | 2.0.4-r0 | — |
| Alpine v3.23 | dnsdist | 2.0.4-r0 | — |
Advisories 4
- WID-SEC-2026-1230 DNSdist: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Aug 5, 2026
- SUSE-SU-2026:22319-1 Security update for dnsdist SUSE / openSUSE Security Updates · Jul 2, 2026
- openSUSE-SU-2026:21015-1 Security update for dnsdist SUSE / openSUSE Security Updates · Jun 30, 2026
- openSUSE-SU-2026:10632-1 dnsdist-2.0.5-1.1 on GA media SUSE / openSUSE Security Updates · Apr 29, 2026