""ET TROJAN W32/GCman.Backdoor CnC Beacon""

SID: 2022529

Revision: 1

Class Type: trojan-activity

Metadata: attack_target Client_Endpoint, created_at 2016_02_17, deployment Perimeter, signature_severity Major, tag c2, updated_at 2016_02_17, 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: "POST"

  • Value: "/cgi-bin/s2.cgi" Depth: 15

  • Value: !"Referer|3A|"

Within:

PCRE: "/^[a-f0-9]{31}\x3B(?:[a-zA-Z0-9+/=]+)?\r?$/P"

Special Options:

  • http_method

  • http_uri

  • http_header

source