Allele Security Alert
Crafted query for meta-types can cause a denial of service
PowerDNS Recursor from 4.0.0 up to and including 4.1.4
PowerDNS Recursor 4.0.9, 4.1.5
Proof of concept
An issue has been found in PowerDNS Recursor where a remote attacker sending a DNS query for a meta-type like OPT can lead to a zone being wrongly cached as failing DNSSEC validation. It only arises if the parent zone is signed, and all the authoritative servers for that parent zone answer with FORMERR to a query for at least one of the meta-types. As a result, subsequent queries from clients requesting DNSSEC validation will be answered with a ServFail.
PowerDNS Security Advisories 2018-03, 2018-04, 2018-05, 2018-06 and 2018-07
PowerDNS Security Advisory 2018-07: Crafted query for meta-types can cause a denial of service
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Last modified: November 8, 2018