alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET HUNTING Base64 Encoded whoami in HTTP Server Response"; flow:established,to_client; file.data; content:"d2hvYW1p"; reference:md5,a6828081717974a89792548e1e31f29a; reference:url,twitter.com/fr0s7_/status/1428326979527381000; classtype:bad-unknown; sid:2033745; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_08_19, deployment Perimeter, performance_impact Low, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_08_19;)