alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Likely Malicious Windows SCT Download MSXMLHTTP M2"; flow:established,from_server; flowbits:isset,et.IE7.NoRef.NoCookie; http.content_type; content:"text/scriptlet"; nocase; fast_pattern; startswith; reference:url,www.carbonblack.com/2016/04/28/threat-advisory-squiblydoo-continues-trend-of-attackers-using-native-os-tools-to-live-off-the-land/; classtype:trojan-activity; sid:2024551; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_08_15, deployment Perimeter, malware_family PowerShell, confidence Medium, signature_severity Major, tag PowerShell_Downloader, updated_at 2020_10_09;)