Unbound before 1.10.1 has Insufficient Control of Network Message Volume aka an "NXNSAttack" issue. This is triggered by random subdomains in the NSDNAME in NS records.

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UBUNTU-CVE-2020-10995

PowerDNS Recursor from 4.1.0 up to and including 4.3.0 does not sufficiently defend against amplification attacks. An issue in the DNS protocol has been found that allow malicious parties to use recursive DNS services to attack third party authoritative name servers. The attack uses a crafted rep...