The PowerDNS nameserver is an authoritative-only nameserver which uses a flexible backend architecture.
It was discovered that PowerDNS did not properly handle certain unknown records.
An authorized attacker with the ability to insert crafted records into a zone might be able to leak the content of uninitialized memory. Crafted records cannot be inserted via AXFR.
Do not take zone data from untrusted users.
All PowerDNS users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-dns/pdns-4.3.1"