Inspired by the potential interesting ideas of the danger theory, a novel security evaluation paradigm for network security, it is called DTPSE, is proposed in this paper. Within DTPSE, computer network attacks are regarded as bacterium, which are dangerous, and induce danger signals through simulating cells undergoing injury, or stress or 'bad cell death'; the network evaluation centre can dynamically aware the security risk by fusion the danger signals received from host-based sensors. Theoretical analysis shows that the proposed paradigm is feasible. Thus, it provides a novel solution to information security risk assessment.