alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Unknown - Loader - Check .exe Updated"; flow:established,to_server; urilen:<10; http.uri; content:".exe"; fast_pattern; http.header; content:"If-Modified-Since|3a 20|"; content:"If-None-Match|3a 20|"; http.user_agent; content:!"PatchManager|20|"; classtype:trojan-activity; sid:2016097; rev:6; metadata:created_at 2012_12_28, confidence Medium, signature_severity Major, updated_at 2022_08_22, reviewed_at 2024_03_25;)