Software-as-a-Service (SaaS) makes use of a cloud computing infrastructure to deliver their applications to many users regardless of their location. Because of this sharing nature SaaS clouds are vulnerable and provide more opportunities for attackers to exploit the system vulnerability and perform strategic attacks. In this paper, the authors present IntTest, an effective service integrity attestation framework for SaaS clouds. IntTest provides an integrated graph attestation analysis method that can pinpoint malicious service providers than existing methods.