""ET TROJAN Cobalt Strike Beacon Activity (GET)""

SID: 2033669

Revision: 2

Class Type: trojan-activity

Metadata: attack_target Client_Endpoint, created_at 2021_08_04, deployment Perimeter, deployment SSLDecrypt, performance_impact Low, signature_severity Major, updated_at 2021_08_04

Reference:

Protocol: tcp

Source Network: $HOME_NET

Source Port: any

Destination Network: $EXTERNAL_NET

Destination Port: $HTTP_PORTS

Flow: established,to_server

Contents:

  • Value: "GET"

  • Value: "Cookie|3a 20|reg_fb_gate="

  • Value: !"Referer|3a 20|"

Within:

PCRE: "/^reg_fb_gate=(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})$/C"

Special Options:

  • http_method

  • fast_pattern

  • http_header

  • http_header

source