alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET RETIRED Potential GCleaner CnC Checkin"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"|2f|advertisting|2f|plus|2e|php|3f|s|3d|NOSUB"; fast_pattern; startswith; content:"str|3d|"; content:"substr|3d|"; bsize:56; http.header_names; content:"|0d 0a|Accept|0d 0a|Accept|2d|Language|0d 0a|Accept|2d|Charset|0d 0a|Accept|2d|Encoding|0d 0a|User|2d|Agent|0d 0a|Host|0d 0a|Connection|0d 0a|Cache|2d|Control|0d 0a 0d 0a|"; http.user_agent; content:"OK"; reference:md5,1f5428d10a51b1247cd0b2565d709264; classtype:trojan-activity; sid:2044034; rev:5; metadata:attack_target Client_and_Server, created_at 2023_01_31, deployment Perimeter, former_category MALWARE, malware_family GCleaner, performance_impact Low, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_09_30, reviewed_at 2024_09_30; target:src_ip;)