CVE-2025-30193: Powerdns Dnsdist

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

In some circumstances, when DNSdist is configured to allow an unlimited number of queries on a single, incoming TCP connection from a client, an attacker can cause a denial of service by crafting a TCP exchange that triggers an exhaustion of the stack and a crash of DNSdist, causing a denial of service. The remedy is: upgrade to the patched 1.9.10 version. A workaround is to restrict the maximum number of queries on incoming TCP connections to a safe value, like 50, via the setMaxTCPQueriesPerConnection setting. We would like to thank Renaud Allard for bringing this issue to our attention.

Affected products

• Powerdns Dnsdist

Published 2025-05-20. Last modified 2026-06-17.