alert tcp $EXTERNAL_NET $HTTP_PORTS -> $HOME_NET any (msg:"ET WEB_CLIENT Possible % Encoded Iframe Tag"; flow:established,to_client; content:"%69%66%72%61%6d%65"; nocase; reference:url,cansecwest.com/slides07/csw07-nazario.pdf; reference:url,www.sophos.com/security/technical-papers/malware_with_your_mocha.html; reference:url,www.guardian.co.uk/technology/2008/apr/03/security.google; classtype:bad-unknown; sid:2012241; rev:2; metadata:affected_product Web_Browsers, affected_product Web_Browser_Plugins, attack_target Client_Endpoint, created_at 2011_01_27, deployment Perimeter, confidence Medium, signature_severity Major, tag Web_Client_Attacks, updated_at 2019_07_26;)