""ET CURRENT_EVENTS [Fireeye] Backdoor.HTTP.BEACON.[Yelp Request]""

SID: 2031289

Revision: 3

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_12_08, deployment Perimeter, signature_severity Major, tag c2, updated_at 2020_12_09, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel

Reference:

Protocol: tcp

Source Network: $HOME_NET

Source Port: any

Destination Network: $EXTERNAL_NET

Destination Port: $HTTP_PORTS

Flow: established,to_server

Contents:

  • Value: "Cookie|3a 20|hl=en|3b|bse="

  • Value: "|3b|_gat_global=1|3b|recent_locations|3b|_gat_www=1|3b|"

Within:

PCRE: "/^hl=en\x3bbse=(?:[a-zA-Z0-9+\/]{4})*(?:[a-zA-Z0-9_\/+-]{2}==|[a-zA-Z0-9_\/+-]{3}=|[a-zA-Z0-9_\/+-]{4})x3b_gat_global=1\x3brecent_locations\x3b_gat_www=1\x3b$/C"

Special Options:

  • http_cookie

source