alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE DonotGroup Template Download"; flow:established,to_server; http.method; content:"HEAD"; http.uri; content:"/jack/"; startswith; fast_pattern; pcre:"/^[a-zA-Z0-9]{32}\.dot$/R"; http.user_agent; content:"Microsoft Office"; http.header_names; content:!"Referer"; reference:md5,82e3981303bee2eff6d1af17ad51eb32; reference:md5,8cc87eb3667aecc1bd41018f00aca559; reference:md5,d4b45f7a937139e05f386a8ad0aba04e; reference:md5,5fdcbb85733f9e8686d582b2f1459961; reference:url,twitter.com/ShadowChasing1/status/1379048935969316871; classtype:trojan-activity; sid:2032483; rev:1; metadata:created_at 2021_04_05, malware_family DonotGroup, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_04_05;)