CVE-2026-71194 Denial of service in Designate
An unauthenticated attacker can cause a denial of service in OpenStack Designate by sending a single UDP packet that triggers a deterministic lookup failure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-71194?
CVE-2026-71194 is a medium-severity denial of service vulnerability in OpenStack Designate, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In OpenStack Designate before 22.0.2, the mDNS handler performs pool-blind lookups when resolving record queries and NOTIFY requests. When two zones with the same name exist across different pools, the lookup fails with a deterministic error, causing the handler to return REFUSED for all DNS queries through that path. The _handle_notify path is exploitable via a single unauthenticated UDP packet. This is independently reachable through the cross-tenant zone overlap described in a different recent CVE, and also affects legitimate same-tenant cross-pool configurations. BIND9 views do not mitigate this issue as mDNS is a shared service upstream of any view configuration.
Weakness: CWE-669
Which versions are affected by CVE-2026-71194?
How do I fix CVE-2026-71194?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-71194 being exploited?
There is no known exploitation of CVE-2026-71194 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-71194, GHSA-r7xh-5qq7-jh72, UBUNTU-CVE-2026-71194.