""ET TROJAN Win32/Umbral-Stealer CnC Exfil via Discord (POST)""

SID: 2045593

Revision: 1

Class Type: trojan-activity

Metadata: affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_05_04, deployment Perimeter, deployment SSLDecrypt, malware_family UmbralStealer, confidence High, signature_severity Major, updated_at 2023_05_04

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: "discord.com|0d 0a|"

  • Value: "|7b 22|title|22 3a 22|Umbral|20|Stealer|22 2c 22|description|22 3a 22|"

  • Value: "|22 2a 2a 5f 5f|System|20|Info|5f 5f 2a 2a 5c|r|5c|n"

  • Value: "|5c|r|5c|n|5c|r|5c|n|2a 2a 5f 5f|Grabbed|20|Data|5f 5f 2a 2a 5c|r|5c|n|60 60 60|"

Within:

PCRE: "/Host\x3a\x20[^\r\n]+discord.com/Hmi"

Special Options:

  • http_method

  • http_header

  • file_data

source