Debian DSA-3664-1 Critical: pdns Denial Of Service Risks

CVE-2016-5426 / CVE-2016-5427

Florian Heinz and Martin Kluge reported that the PowerDNS
Authoritative Server accepts queries with a qname's length larger
than 255 bytes and does not properly handle dot inside labels. A
remote, unauthenticated attacker can take advantage of these flaws
to cause abnormal load on the PowerDNS backend by sending specially
crafted DNS queries, potentially leading to a denial of service.

CVE-2016-6172

It was reported that a malicious primary DNS server can crash a
secondary PowerDNS server due to improper restriction of zone size
limits. This update adds a feature to limit AXFR sizes in response
to this flaw.

For the stable distribution (jessie), these problems have been fixed in
version 3.4.1-4+deb8u6.

We recommend that you upgrade your pdns packages.

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/