""ET TROJAN Cobalt Strike Malleable C2 (Unknown Profile)""

SID: 2032953

Revision: 2

Class Type: trojan-activity

Metadata: attack_target Client_Endpoint, created_at 2021_05_13, deployment Perimeter, malware_family Cobalt_Strike, signature_severity Major, updated_at 2021_05_14, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation

Reference:

  • md5

  • b210c0f7687a9199de870e0cc11996c1

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: "//scs/mail-static//js/"

  • Value: "Accept|3a 20|text/html,application/xhtml+xml,application/xml|3b|q=0.9,/|3b|q=0.8|0d 0a|Accept-Language|3a 20|en-US,en|3b|q=0.5|0d 0a|Accept-Encoding|3a 20|gzip, deflate|0d 0a|DNT|3a 20|1|0d 0a|"

  • Value: "OSID=" Depth: 5

Within:

PCRE: "/^OSID=[a-zA-Z0-9\/+]{171}=$/C"

Special Options:

  • http_method

  • fast_pattern

  • http_uri

  • http_header

  • http_cookie

source