This document is about PowerDNS 4.X. If you have PowerDNS 3.X, please see the PowerDNS 3.X documentation

PowerDNS Security Advisory 2016-04: Insufficient validation of TSIG signatures

Two issues have been found in PowerDNS Authoritative Server allowing an attacker in position of man-in-the-middle to alter the content of an AXFR because of insufficient validation of TSIG signatures. The first issue is a missing check of the TSIG time and fudge values in AXFRRetriever, leading to a possible replay attack. This issue has been assigned CVE-2016-7073. The second issue is a missing check that the TSIG record is the last one, leading to the possibility of parsing records that are not covered by the TSIG signature. This issue has been assigned CVE-2016-7074.

PowerDNS Authoritative Server up to and including 3.4.10 and 4.0.1 are affected. PowerDNS Recursor from 4.0.0 up to and including 4.0.3 are affected.

For those unable to upgrade to a new version, a minimal patch is available

We would like to thank Mongo for finding and subsequently reporting this issue.