alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Jupyter Stealer CnC Checkin"; flow:established,to_server; http.start; content:"POST / HTTP/1.1|0d 0a|Host|3a 20|"; startswith; http.host.raw; pcre:"/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/"; http.header_names; content:"|0d 0a|Host|0d 0a|Content-Length|0d 0a|Connection|0d 0a 0d 0a|"; bsize:38; fast_pattern; http.content_len; byte_test:0,>=,200,0,string,dec; byte_test:0,<=,999,0,string,dec; http.connection; content:"Keep-Alive"; bsize:10; http.request_body; content:!"|0d 0a|"; pcre:"/^[\x20-\x7e\r\n]{0,20}[^\x20-\x7e\r\n]/"; reference:url,blog.morphisec.com/new-jupyter-evasive-delivery-through-msi-installer; reference:md5,c4772d76029004a5512ea6e2ff3be39b; classtype:command-and-control; sid:2034024; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_09_24, deployment Perimeter, malware_family Jupyter, performance_impact Significant, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_09_28;)