Combing with the characteristics of embedded device firmwares,an improved fuzzy test method was proposed.After analyzing the attack surface of the firmwares from the standpoint of exploits utilization,several security rules were derived.By introducing the crisis weights of test cases in taint analytical results,a set of fuzzy test cases that are corresponding to crisis weights was designed.The method was used to dig vulnerabilities in popular equipments,and many zero-day exploits were found.Experimental results showed that this method is effective and practical.
