alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"REMOTE [PTsecurity] XWorm"; flow:established, to_server; dsize:228; stream_size:server, <, 3; stream_size:client, =, 229; content:"224|00|"; depth:4; isdataat:223, relative; isdataat:!225, relative; content:!"|7c 27 7c|"; content:!"|7c|yes"; nocase; content:!"|7c|win"; nocase; content:!"|7c|no"; nocase; reference:url, rules.ptsecurity.com; classtype:trojan-activity; sid:10013753; rev:2;)