alert tcp $EXTERNAL_NET any -> $SMTP_SERVERS 25 (msg:"ET MALWARE UPS Inbound bad attachment v.6"; flow:established,to_server; content:"From|3a| |22|United Parcel Service|22|"; nocase; content:"|40|ups.com"; nocase; content:"Content-Disposition|3a| attachment|3b|"; nocase; content:"filename=|22|document.zip|22|"; nocase; classtype:trojan-activity; sid:2012444; rev:3; metadata:created_at 2011_03_09, signature_severity Major, updated_at 2019_07_26;)