alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE TA450 Nagual CnC Activity"; flow:established,to_server; urilen:<50; http.method; content:"POST"; http.uri; pcre:"/^\/[a-z]+/"; http.content_type; content:"application/x-www-form-urlencoded"; bsize:33; http.header; content:"CharSet|3a 20|UTF-8|0d 0a|"; fast_pattern; http.request_body; content:"vl="; startswith; pcre:"/^[0-9D]+$/R"; reference:md5,b0ab12a5a4c232c902cdeba421872c37; classtype:command-and-control; sid:2034325; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_11_02, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, tag TA450, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_11_02;)