MGASA-2019-0009

A vulnerability was in found in PowerDNS Recursor. The issue is a memory leak occurring while parsing some malformed records, due to the fact that some memory is allocated parsing a record and is not always properly released if the record is not valid. It allows a malicious auth server to cause a denial of service by sending specially crafted records in response to a legitimate query by an authorized user (CVE-2018-10851).

An issue has been found in PowerDNS Recursor allowing a remote user to craft a DNS query that will cause an answer without DNSSEC records to be inserted into the packet cache and be returned to clients asking for DNSSEC records, thus hiding the presence of DNSSEC signatures for a specific qname and qtype. For a DNSSEC-signed domain, this means that clients performing DNSSEC validation by themselves might consider the answer to be bogus until it expires from the packet cache, leading to a denial of service (CVE-2018-14626).

An issue has been found in PowerDNS Recursor from 4.0.0 up to and including 4.1.4. 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 (CVE-2018-14644).

An issue has been found in PowerDNS Recursor where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash (CVE-2018-16855).