alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Sefnit Checkin 5"; flow:established,to_server; http.uri; content:"?subid="; fast_pattern; content:"&u="; distance:0; pcre:"/\?subid=\d{9}&u=[\w\.\-]{23}$/i"; classtype:command-and-control; sid:2014248; rev:4; metadata:created_at 2012_02_21, signature_severity Major, updated_at 2024_03_19;)