Minimizing information leakage in the DNS

Abstract

The domain name system is the global lookup service for network resources. To protect DNS information, the DNS security extensions have been developed and deployed on branches of the DNS to provide authentication and integrity protection using digital signatures. However, signed DNS nodes were found to have an unfortunate side effect: an attacker can query them as reconnaissance before attacking hosts on a particular network. There are different ways a zone administrator can minimize information leakage and still take advantage of DNSSEC for integrity and source authentication. This article describes the risk and examines the protocol and operational options and looks at their advantages and drawbacks.