Attacks on port knocking authentication mechanism

Abstract

Research in authentication mechanisms has led to the design and development of new schemes. The security provided by these procedures must be reviewed and analyzed before they can be widely used. In this paper, we analyze some weaknesses of the port knocking authentication method that makes it vulnerable to many attacks. We will present the NAT-Knocking attack, in which an unauthorized user can gain access to the protected server just by being in the same network than an authorized user. We will also discuss the DoS-Knocking attack, which could lead to service disruptions due to attackers "knocking" on many ports of the protected server. Finally, we will review further implementation issues. © Springer-Verlag Berlin Heidelberg 2005.