Reporter: Qifan Zhang, Palo Alto Networks
When validating DNSSEC responses, public keys are compared against trust anchors without regard for the name of the DNSKEY record they are contained in. If all DNSKEYs in an RRset are trusted public keys, verification will succeed without checking any RRSIGs. The impact of this issue is that any secure zone's DNSKEY RRset can be tampered with by replacing public keys with the root zone's public keys without detection. The temporal impact of this tampering can be extended past the initial response spoofing/control of name server by using a large TTL so that the modified DNSKEY RRset is cached for longer. Further forgery beyond the DNSKEY RRset is not possible, as that would require signatures by those keys.
Reporter: Qifan Zhang, Palo Alto Networks
When validating DNSSEC responses, public keys are compared against trust anchors without regard for the name of the DNSKEY record they are contained in. If all DNSKEYs in an RRset are trusted public keys, verification will succeed without checking any RRSIGs. The impact of this issue is that any secure zone's DNSKEY RRset can be tampered with by replacing public keys with the root zone's public keys without detection. The temporal impact of this tampering can be extended past the initial response spoofing/control of name server by using a large TTL so that the modified DNSKEY RRset is cached for longer. Further forgery beyond the DNSKEY RRset is not possible, as that would require signatures by those keys.