SecurID Vulnerabilities White-Paper Due to increased recent interest that has been witnessed on the net about the SecurID token cards and potential vulnerabilities with their use, we offer a white paper on some of the vulnerabilities that we believe have been witnessed and/or speculated upon. This paper is being put forth into the public domain by Secure Networks Incorporated and is available at the following URL : ftp://ftp.secnet.com/pub/papers/securid.ps Topics dealt with in the paper include: . Race attacks based upon fixed length responses (still valid even with the current patch) . Denial of Service attacks based upon server patches . Server - Slave separation and replay attacks . Vulnerabilities in the communications with the ACE Server . A quick analysis of the communications with the ACE Server . Problems with out-of-band authentication We hope this paper provides insight, enlightenment, and is helpful to the security community in general. thanks and enjoy, Secure Networks Inc.