alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET PHISHING Shared Document Base64 Phishing Landing 2016-01-20"; flow:established,from_server; http.stat_code; content:"200"; http.content_type; content:"text/html"; startswith; file.data; content:"data|3a|text/html|3b|base64"; nocase; fast_pattern; content:"PCFET0NUWVBFIGh0bWw+"; distance:1; within:21; reference:md5,0c9a677efd2762c4d5d759c294bc00d7; classtype:social-engineering; sid:2032175; rev:5; metadata:attack_target Client_Endpoint, created_at 2016_01_20, deployment Perimeter, confidence Medium, signature_severity Major, tag Phishing, updated_at 2020_08_04;)