alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Possible DarkHotel Landing M2"; flow:established,to_client; file_data; content:"HTA|3a|APPLICATION"; nocase; fast_pattern; content:"|22|&#x"; content:"classid"; nocase; pcre:"/^\s*?=\s*?[\x22\x27](?:c|&#(?:x[64]3|99|67)\x3b)(?:l|&#(?:x[64]c|108|76)\x3b)(?:s|&#(?:x[75]3|115|83)\x3b)(?:i|&#(?:x[64]9|105|73)\x3b)(?:d|&#(?:x[64]4|100|68)\x3b)(?:\x3a|&#(?:x3a|58)\x3b)(?![a-fA-F0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12})[^\x22\x27]+(?:(?:\x5c|&#)(?:5[01234567]|10[012]|6[5678]|4[589]|9[789]|7[09])|(?:\x25|&#x)(?:4[123456]|6[123456]|3\d|2D))/Rsi"; reference:url,securelist.com/blog/research/71713/darkhotels-attacks-in-2015/; classtype:targeted-activity; sid:2021611; rev:4; metadata:created_at 2015_08_11, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_10_08;)