CVE-2025-30194: Powerdns Dnsdist

High severity, CVSS 7.5. EPSS: 2.3% chance of exploitation in the next 30 days.

When DNSdist is configured to provide DoH via the nghttp2 provider, an attacker can cause a denial of service by crafting a DoH exchange that triggers an illegal memory access (double-free) and crash of DNSdist, causing a denial of service. The remedy is: upgrade to the patched 1.9.9 version. A workaround is to temporarily switch to the h2o provider until DNSdist has been upgraded to a fixed version. We would like to thank Charles Howes for bringing this issue to our attention.

Affected products

• Powerdns Dnsdist: from 1.9.0, before 1.9.9 (fixed in 1.9.9)

Published 2025-04-29. Last modified 2026-06-17.