When Parents and Children Disagree: Diving into DNS Delegation Inconsistency
Raffaele Sommese, Giovane Moura, Mattijs Jonker, Roland van Rijswijk-Deij, Alberto Dainotti, Kimberly Claffy, Anna Sperotto
PAM2020 Passive and Active Measurement Conference
The Domain Name System (DNS) is a hierarchical, decentralized, and distributed database. A key mechanism that enables the DNS to be hierarchical and distributed is delegation  of responsibility from parent to child zones—typically managed by different entities. RFC1034  states that authoritative nameserver (NS) records at both parent and child should be “consistent and remain so”, but we find inconsistencies for over 13M second-level domains. We classify the type of inconsistencies we observe, and the behavior of resolvers in the face of such inconsistencies, using RIPE Atlas to probe our experimental domain configured for different scenarios. Our results underline the risk such inconsistencies pose to the availability of misconfigured domains.
The Forgotten Side of DNS: Orphan and Abandoned Records
Raffaele Sommese, Mattijs Jonker, Roland van Rijswijk-Deij, Alberto Dainotti, Kimberly Claffy, Anna Sperotto
WTMC2020 5th International Workshop on Traffic Measurements for Cybersecurity
DNS zone administration is a complex task involving manual work and several entities and can therefore result in misconfigurations. Orphan records are one of these misconfigurations, in which a glue record for a delegation that does not exist anymore is forgotten in the zone file. Orphan records are a security hazard to third-party domains that have these records in their delegation, as an attacker may easily hijack such domains by registering the domain associated with the orphan. The goal of this paper is to quantify this misconfiguration, extending previous work by Kalafut et al., by identifying a new type of glue record misconfiguration – which we refer to as abandoned records – and by performing a broader characterization. Our results highlight how the situation has changed, not always for the better, compared to a decade-old study.