Nonce-based Kerberos is a Secure Delegated AKE Protocol

Abstract. Kerberos is one of the most important cryptographic protocols, first because it is the basisc authentication protocol in Microsoft’s Active Directory and shipped with every major operating system, and second because it served as a model for all Single-Sign-On protocols (e.g. SAML, OpenID, MS Cardspace, OpenID Connect). Its security has been confirmed with several Dolev-Yao style proofs [1–12], and attacks on certain versions of the protocol have been described [13,14]. However despite its importance, despite its longevity, and despite the wealth of Dolev-Yao-style security proofs, no reduction based security proof has been published until now. This has two reasons: (1) All widely accepted formal models either deal with two-party protocols, or group key agreement protocols (where all entities have the same role), but not with 3-party protocols where each party has a different role. (2) Kerberos uses timestamps and nonces, and formal security models for timestamps are no...

• Type: Journal
• Year: 2016
• Where: IACR
• Authors: Jörg Schwenk
• Keywords: Biometrics, IACR 2016