Florian Heinz

**Name of the Vulnerable Software and Affected Versions** PowerDNS versions prior to 3.4.11 and 4.0.2 PowerDNS recursor versions prior to 3.7.4 and 4.0.4 **Description** The issue allows a remote, unauthenticated attacker to cause an abnormal CPU usage load on the PowerDNS server by sending crafted DNS queries. This could result in a partial denial of service if the system becomes overloaded. The problem is based on the fact that the PowerDNS server parses all records present in a query regardless of whether they are needed or even legitimate. A specially crafted query containing a large number of records can be used to take advantage of that behavior. **Recommendations** For PowerDNS versions prior to 3.4.11 and 4.0.2, update to version 3.4.11 or 4.0.2 or later to resolve the issue. For PowerDNS recursor versions prior to 3.7.4 and 4.0.4, update to version 3.7.4 or 4.0.4 or later to resolve the issue. As a temporary workaround, consider restricting access to the PowerDNS server to minimize the risk of exploitation.

**Name of the Vulnerable Software and Affected Versions** PowerDNS (aka pdns) Authoritative Server versions prior to 3.4.10 **Description** The issue allows remote attackers to cause a denial of service by consuming backend CPU resources via a long `qname`. **Recommendations** For versions prior to 3.4.10, update to version 3.4.10 or later to resolve the issue.