alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE slock Ransomware CnC Activity"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/slock.php?ip="; fast_pattern; content:"&&user="; distance:0; content:"&&host="; distance:0; content:"&&domain="; distance:0; http.user_agent; content:"Mozilla|2f|5|2e|0|20 28|Windows|20|NT|20|10|2e|0|3b 20|WOW64|3b 20|Trident|2f|7|2e|0|3b 20|rv|3a|11|2e|0|29 20|like|20|Gecko"; bsize:69; reference:md5,45a430e2bcba867f4d8a537354a98a73; classtype:command-and-control; sid:2034291; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_10_29, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag Ransomware, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_10_29, mitre_tactic_id TA0040, mitre_tactic_name Impact, mitre_technique_id T1486, mitre_technique_name Data_Encrypted_for_Impact;)