Research on cache-based side-channel attacks shows the security impact of these attacks on cloud computing. Therefore , the detection of cache-based side-channel attacks has received more attention in IaaS cloud infrastructures because of improvements in the attack techniques. However, such detection requires high resolution information, and it is also a challenging task because of the fine-granularity of the attacks. In this paper, we present an approach to detect cross-VM cache-based side-channel attacks through using hardware fine-grained information provided by Intel Cache Monitoring Technology (CMT) and Hardware Performance Counters (HPCs) following the Gaussian anomaly detection method. The approach shows a high detection rate with 2% performance overhead on the computing platform.