Wireless Sensor Network (WSN) is a rising technology for real-time applications to track and monitor environmental and physical parameters. Due to the properties of sensor nodes such as small size, low cost, wireless communication, processing capability, it is widely used in military and public applications. The WSN system deals with real time data, so it becomes prone to various attacks at each level, such as; jamming, tampering, collision, overwhelm, repudiation, monitoring and eavesdropping, flooding, session hijacking, wormhole, black hole, gray hole, sinkhole, Byzantine, and Sybil attack. The paper aggregates all possible attacks at each layer of the WSN protocol stack. It also briefs the major security issues and the possible attacks on WSN system. Finally, the paper is enveloped with a brief discussion on open research challenges.

WSN Security challenges, WSN Protocol stack, Attacks based on layers, open research challenges in WSN Security