Security Evaluation of Scenarios Based on the TCG’s TPM Specification

Abstract

Abstract. The Trusted Platform Module TPM is a basic but nevertheless very complex security component that can provide the foundations and the root of security for a variety of applications. In contrast to the TPM, other basic security mechanisms like cryptographic algorithms or security protocols have frequently been subject to thorough security analysis and formal verification. This paper presents a first methodic security analysis of a large part of the TPM specification. A formal automata model based on asynchronous product automata APA and a finite state verification tool SHVT are used to emulate a TPM within an executable model. On this basis four different generic scenarios were analysed with respect to security and practicability: secure boot, secure storage, remote attestation and data migration. A variety of security problems and inconsistencies was found. Subsequently, the TPM specification was adapted to overcome the problems identified. In this paper, the analysis of the remote attestation scenario and some of the problems found are explained in more detail.

Attack, Solution and Verification for Shared Authorisation Data in TCG TPM

“…Therefore, the ITadmin can successfully impersonate the TPM just because it knows the authdata of SRK. The attack scenario given in this example, in which ITadmin is the attacker, is similar to that illustrating the TPM CertifyKey attack in [12]. Many other scenarios are possible.…”

“…An attacker can in some circumstances illegitimately obtain a certificate on a TPM key of his choice [12]. Also, an attacker can intercept a message, aiming to cause the legitimate user to issue another one, and then cause both to be received, resulting in the message being processed twice [10].…”

Dynamic Measurement and Protected Execution: Model and Analysis

“…Lin considered modelling PCR state, but was unable to do this with Otter. Gurgens et al [9] describe an analysis of the TPM API using a finite state automata, but the model fragment given does not appear to consider PCR state and the analysis in the paper is predominantly informal. Coker et al [3] focus on the analysis of TPM APIs for remote attestation, but their SAL model is not yet publicly available.…”

Web Service Assurance: The Notion and the Issues

“…Finally, the project ASSERT4SOA (Advanced Security Service cERTificate for SOA) aims to define and develop a certification infrastructure dealing with both test-based and model-based certification to provide a certificate-aware SOA [41]. Gürgens and Rudolph proposed another interesting approach to find security flaws in a number of key exchange, authentication, and non-repudiation protocols [42][43][44]. Their approach is supported by the Simple Homomorphism Verification Tool [45].…”