alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET EXPLOIT_KIT KaiXin Landing M5 1 Oct 05 2015"; flow:established,from_server; file_data; content:"str2long"; fast_pattern; content:"long2str"; content:"0xffffffff"; pcre:"/^(?P<sep>[^\s\x3b\x22\x27])(?=.+?(?P=sep)str2long(?P=sep)).+?(?P=sep)long2str(?P=sep)/Rs"; classtype:exploit-kit; sid:2021905; rev:3; metadata:created_at 2015_10_06, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_10_08;)