alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Mespinoza Ransomware - Pre-Encryption File Exfil to CnC"; flow:established,to_server; http.uri; content:"/upload-"; startswith; fast_pattern; content:"?token="; pcre:"/^(?:[A-Z0-9+/]{4})*(?:[A-Z0-9+/]{2}==|[A-Z0-9+/]{3}=|[A-Z0-9+/]{4})/R"; content:"&id="; distance:0; content:"&fullPath="; distance:0; reference:url,unit42.paloaltonetworks.com/gasket-and-magicsocks-tools-install-mespinoza-ransomware/; classtype:command-and-control; sid:2033343; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_07_15, deployment Perimeter, malware_family Mespinoza, confidence High, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_07_15, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)