Versions (3)
Version DetailsCurrent
Rev: 5 • Sep 23, 2015, 12:00 PMET MALWARE Ursnif Variant CnC Beacon 2
alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Ursnif Variant CnC Beacon 2"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/upx/"; fast_pattern; pcre:"/\/(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/\x20]{2}==|[A-Za-z0-9+/\x20]{3}=|[A-Za-z0-9+/\x20]{4})$/"; http.user_agent; content:"Mozilla/"; startswith; http.header_names; content:!"|0d 0a|Accept"; content:!"|0d 0a|Referer|0d 0a|"; content:"|0d 0a|User-Agent|0d 0a|"; startswith; reference:md5,f48f626cf746a2c3c73182c752c481b6; reference:md5,8ab21ac9199d3ced2230924b90f49f0d; classtype:command-and-control; sid:2021812; rev:5; metadata:attack_target Client_Endpoint, created_at 2015_09_23, deployment Perimeter, signature_severity Major, tag c2, updated_at 2024_03_11, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)
Sep 23, 2015, 12:00 PM
Mar 11, 2024, 12:00 PM
Sep 21, 2024, 3:00 AM
May 30, 2025, 12:04 AM
rules/emerging-malware.rules