alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Possible MSXMLHTTP Request (msi) unset (no exe)"; flow:to_server,established; flowbits:isset,et.MS.XMLHTTP.no.exe.request; flowbits:unset,et.MS.XMLHTTP.no.exe.request; flowbits:noalert; http.uri; content:".msi"; nocase; fast_pattern; classtype:misc-activity; sid:2022265; rev:6; metadata:created_at 2015_12_15, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_10_05;)