""ET TROJAN Chafer Win32/TREKX Uploading to CnC (Modified CAB)""

SID: 2027480

Revision: 2

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, created_at 2019_06_17, deployment Perimeter, malware_family TREKX, performance_impact Low, signature_severity Major, tag Chafer, tag APT39, updated_at 2019_06_17

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: ".aspx"

  • Value: "multipart|2f|form-data|3b|"

  • Value: "Content-Disposition|3a 20|form-data|3b|"

  • Value: "TREC"

  • Value: !"Referer|3a|"

Within:

PCRE: "/^[\x20-\x7e\r\n]{0,13}[^\x20-\x7e\r\n]/Rs"

Special Options:

  • http_method

  • http_uri

  • http_header

  • http_client_body

  • http_client_body

  • fast_pattern

  • http_header

source