Secure Coprocessor Integration with Kerberos V5

Abstract

The nightmare of Trusted Third Party (t3P) based protocol users is compromise of the T3P. Because the compromised T3P can read and modify any user information, the entire user group becomes vulnerable to secret revelation and user impersonation. Kerberos, the most widely used network authentication protocol, is no exception. When the Kerberos Key Distribution Center (KDC) is compromised, all the user keys are exposed, thus revealing all the encrypted data and allowing an adversary to impersonate any user. If an adversary has physical access to the KDC host, or can obtain administrator rights, KDC compromise is possible and catastrophic. To solve this problem, and to demonstrate the capabilities of secure hardware, we have integrated the IBM 4758 secure coprocessor into Kerberos V5 KDC. As a result of the integration, our implemented KDC preserves security even if the KDC host has been compromised.