""ET TROJAN FormBook CnC Checkin (GET)""

SID: 2031412

Revision: 9

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_12_19, deployment Perimeter, malware_family Formbook, performance_impact Significant, signature_severity Major, updated_at 2023_08_10, reviewed_at 2024_02_13

Reference:

  • md5

  • a6a114f6bc3e86e142256c5a53675d1a

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: "/?"

  • Value: "Host|3a 20|" Depth: 6

  • Value: "Connection|3a 20|close|0d 0a 0d 0a|"

Within:

PCRE: "/^Host\x3a\x20[^\r\n]+\r\nConnection\x3a\x20close\r\n\r\n$/Hmi"

Special Options:

  • http_method

  • http_uri

  • http_header

  • http_header

source