alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE HAWKBALL CnC Initial Request"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/?t="; depth:4; content:"&&s="; distance:0; content:"&&p="; distance:0; content:"&&k="; distance:0; fast_pattern; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|MSIE 8.0|3b 20|Windows NT 6.1|3b 20|Trident/4.0|3b 20|SLCC2|3b 20|.NET CLR 2.0.50727|3b 20|.NET CLR 3.5.30729|3b 20|.NET CLR 3.0.30729|3b 20|Media Center PC 6.0|3b 20|InfoPath.2)"; http.content_len; byte_test:0,=,0,0,string,dec; http.header_names; content:"|0d 0a|Content-Length|0d 0a|Cache-Control|0d 0a|User-Agent|0d 0a|Host|0d 0a|Connection|0d 0a 0d 0a|"; depth:65; endswith; reference:md5,d90e45fbf11b5bbdca945b24d155a4b2; reference:url,www.fireeye.com/blog/threat-research/2019/06/government-in-central-asia-targeted-with-hawkball-backdoor.html; classtype:command-and-control; sid:2027439; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_06_06, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_11_09;)