dnsdist -- Transfer requests received over DoH can lead to a denial of service

PowerDNS Security Advisory reports:

When incoming DNS over HTTPS support is enabled using the nghttp2 provider,
and queries are routed to a tcp-only or DNS over TLS backend, an attacker can
trigger an assertion failure in DNSdist by sending a request for a zone transfer (AXFR
or IXFR) over DNS over HTTPS, causing the process to stop and thus leading to a
Denial of Service. DNS over HTTPS is not enabled by default, and backends are using
plain DNS (Do53) by default.