alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Bitter APT CHM CnC Activity (GET) M4"; flow:established,to_server; http.uri; content:".php?zh="; fast_pattern; content:"|2a|"; http.user_agent; content:"Windows Installer"; bsize:17; reference:url,twitter.com/suyog41/status/1686298387455283200; classtype:trojan-activity; sid:2047021; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_08_02, deployment Perimeter, confidence High, signature_severity Critical, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_08_02;)