The NXNSAttack Method is a new flaw impacting DNS protocol that can be exploited to launch amplified, large-scale distributed denial-of-service (DDoS) attacks. The flaw hinges on the DNS delegation mechanism to force DNS resolvers to generate more DNS queries to authoritative servers of attacker’s choice, potentially causing a botnet-scale disruption to online services. PowerDNS, Google, Amazon, Microsoft, Oracle-owned Dyn, Verisign, and IBM Quad9 have patched their software to address the problem.
Source: https://thehackernews.com/2020/05/dns-server-ddos-attack.html