""ET TROJAN Cobalt Strike Malleable C2 (Microsoft Update GET)""

SID: 2032752

Revision: 2

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_09_18, deployment Perimeter, deployment SSLDecrypt, malware_family Cobalt_Strike, signature_severity Major, updated_at 2020_09_18, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation

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: "/c/msdownload/update/others/2016/12/29136388_" Depth: 45

  • Value: ".cab"

  • Value: "User-Agent|3a 20|Windows-Update-Agent/10.0.10011.16384 Client-Protocol/1.40|0d 0a|"

  • Value: !"Referer|3a|"

Within:

PCRE:

Special Options:

  • http_method

  • http_uri

  • http_uri

  • http_header

  • http_header

source