alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE lu0bot Loader HTTP Request M2"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/?"; pcre:"/^[a-f0-9]{5,12}&a=/R"; content:"&a=|20|Mozilla/4.0|20|"; fast_pattern; http.user_agent; content:"Mozilla|2f|4|2e|0|20 28|compatible|3b 20|Win32|3b 20|WinHttp|2e|WinHttpRequest|2e|5|29|"; bsize:57; reference:url,fumik0.com/2021/06/24/lu0bot-an-unknown-nodejs-malware-using-udp/; reference:md5,a86f56aa7d6ce07b9639cf34e798b102; classtype:command-and-control; sid:2034516; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_11_19, deployment Perimeter, malware_family lu0bot, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_11_19;)