There are 2 open security issues in buster.
2 issues left for the package maintainer to handle:
(postponed; to be fixed through a stable update)
In PowerDNS Recursor versions up to and including 4.3.1, 4.2.2 and 4.1.16, the ACL restricting access to the internal web server is not properly enforced.
An issue has been found in PowerDNS Recursor before 4.1.18, 4.2.x before 4.2.5, and 4.3.x before 4.3.5. A remote attacker can cause the cached records for a given name to be updated to the Bogus DNSSEC validation state, instead of their actual DNSSEC Secure state, via a DNS ANY query. This results in a denial of service for installation that always validate (dnssec=validate), and for clients requesting validation when on-demand validation is enabled (dnssec=process).
You can find information about how to handle these issues in the security team's documentation.