alert tcp $HOME_NET any -> $EXTERNAL_NET 1863 (msg:"ET CHAT Possible MSN Messenger File Transfer"; flow:established,from_client; content:"x-msnmsgrp2p"; nocase; content:"appid|3a|"; nocase; pcre:"/appid\x3a\s+2/i"; reference:url,www.hypothetic.org/docs/msn/client/file_transfer.php; classtype:policy-violation; sid:2008289; rev:5; metadata:created_at 2010_07_30, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)