alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/IceXLoader Sending Command Acknowledgement (POST)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:".php"; endswith; http.user_agent; pcre:"/^[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}$/"; http.request_body; content:"Done="; startswith; fast_pattern; http.header_names; content:!"Referer"; reference:url,www.fortinet.com/blog/threat-research/new-icexloader-3-0-developers-warm-up-to-nim; reference:md5,54fb25c20d4191ff7e5185812485282f; classtype:command-and-control; sid:2037044; rev:1; metadata:attack_target Client_Endpoint, created_at 2022_06_21, deployment Perimeter, malware_family IceXLoader, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_06_21;)