alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Dridex Download 6th Jan 2016 Flowbit"; flow:established,to_server; flowbits:set,et.dridexdoc; flowbits:noalert; http.method; content:"POST"; http.uri; content:".php"; endswith; http.content_len; byte_test:0,=,0,0,string,dec; http.user_agent; content:"MSIE 7.0"; fast_pattern; http.host; pcre:"/^\d{1,3}\x2e\d{1,3}\x2e\d{1,3}\x2e\d{1,3}(?:\x3a\d{1,5})?$/"; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; classtype:trojan-activity; sid:2022339; rev:5; metadata:created_at 2016_01_07, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_27;)