alert tcp $HOME_NET any -> any any (msg:"ET MALWARE Win32/ElectricFish Authentication Packet Observed"; flow:established,to_server; content:"aaaabbbbccccdddd|00 00 00 00 00 00 00 00|"; depth:24; fast_pattern; content:"|00 00 04 00 00 00|"; distance:2; within:6; reference:url,www.us-cert.gov/ncas/analysis-reports/AR19-129A; classtype:trojan-activity; sid:2027340; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, created_at 2019_05_09, deployment Perimeter, deployment Internal, malware_family ElectricFish, performance_impact Low, confidence Medium, signature_severity Major, tag APT, tag T1090, tag connection_proxy, updated_at 2019_07_26;)