alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET POLICY Android Dalvik Executable File Download"; flow:established,to_client; file_data; content:"dex|0A|"; within:4; reference:url,source.android.com/tech/dalvik/dex-format.html; classtype:policy-violation; sid:2016856; rev:2; metadata:created_at 2013_05_16, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)