alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT_KIT Possible Nuclear EK Nov 13 2015 Landing URI struct"; flow:established,to_server; urilen:>25; content:"_id="; http_uri; fast_pattern; pcre:"/^\/(?:[a-z0-9]+\/)?[^\x2f]+\?[a-z]{1,40}_id=\d{2,5}(?:&[a-z]{1,40}_id=\d{2,5})?&[^&\x3d]+=(?=[a-z0-9]*?[A-Z])(?=[A-Z0-9]*?[a-z])[A-Za-z0-9]{15,}\x2e{0,2}?$/U"; pcre:"/^Host\x3a\x20[a-z0-9]+\.(?:g[aq]|cf|ml|tk|xyz|info|space)(?:\x3a\d{1,5})?\r$/Hm"; content:!"|0d 0a|Cookie|3a|"; flowbits:set,NuclearEK; classtype:exploit-kit; sid:2022090; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2015_11_13, deployment Perimeter, malware_family Nuclear, confidence Medium, signature_severity Critical, tag Exploit_Kit, tag Nuclear, updated_at 2019_10_08;)