An issue has been found in PowerDNS before 3.4.11 and 4.0.2, and PowerDNS recursor before 4.0.4, allowing an attacker in position of man-in-the-middle to alter the content of an AXFR because of insufficient validation of TSIG signatures. A missing check of the TSIG time and fudge values was found in AXFRRetriever, leading to a possible replay attack.