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

SID: 2032335

Revision: 3

Class Type: trojan-activity

Metadata: attack_target Client_Endpoint, created_at 2021_03_25, deployment Perimeter, performance_impact Significant, signature_severity Major, tag c2, updated_at 2024_04_04, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel

Reference:

  • md5

  • 9e97ace1f585b0914f99fde7014ed8c5

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: ".css"

  • Value: "Cookie|3a 20|SSID="

  • Value: !"Referer|3a 20|"

Within:

PCRE: "/User-Agent[^\r\n]+\r\nConnection[^\r\n]+\r\nCache-Control[^\r\n]+[\r\n]+$/H"

Special Options:

  • http_method

  • http_uri

  • fast_pattern

  • http_header

source