Abstract: WSNs are spatially distributed autonomous sensors to monitor physical or environmental conditions such as temperature sound pressure etc. They are highly prone to malicious attacks and security threats[12][13] since their structures are not predetermined. Malicious attack on the sense that it makes the sensor nodes to drop the packets of data when moved from one node to another. This will surely degrade the performance of the whole system. Another major issue is to distinguish malicious attack from normal packet loss. Most cases we fail to realize malicious attack from normal packet loss. In order to overcome that problem we adopt a new method using threshold value called Channel Aware Anti Malicious Threshold System(CAMTS).