✕
Request a Demo
Rewterz
Rewterz Threat Advisory – Apache OFBiz IDOR Multiple Security Vulnerabilities
July 17, 2020
Rewterz
Rewterz Threat Alert – Try2Cry Ransomware – IOCs
July 18, 2020

Rewterz Threat Alert – The Tetrade: Brazilian Banking Malware Goes Global

Severity

Medium

Analysis Summary

The Tetrade is coined for four large banking trojan families created, developed and spread by Brazilian threat actors on a global level. Brazilian banking trojans have evolved greatly, with hackers adopting techniques for bypassing detection, creating highly modular and obfuscated malware, and using a very complex execution flow, which makes analysis a painful, tricky process. These four banking trojan families: Guildma, Javali, Melcoz and Grandoreiro, are now fully developed and are expanding abroad. Guildma spreads rely heavily on malspam containing a malicious file in compressed format, attached to the email body. File types vary from Visual Basic Script to LNK. Most of the phishing messages emulate business requests, packages sent over courier services or any other regular corporate subjects, including the COVID-19 pandemic, but always with a corporate appearance.

Impact

  • Information Theft
  • Unauthorized Remote Access
  • Detection Evasion
  • Financial Theft

Indicators of Compromise

MD5

  • 1b50b1e375244ce5d4e690cf0dbc96d8
  • 071d3d6404826c24188dc37872224b3d
  • c63b4eb3067d8cb5f2d576bc0777e87d
  • aeaf7355604685d4d753d21902ff1c1c
  • 4194162fe30a3dca6d8568e72c71ed2d
  • 0931a26d44f0e7d70fda9ef86ee203f4
  • 0219ef20ab2df29b9b29f8407cf74f1c

SHA-256

  • 4457ba582eca79b16186855ff3dd53ae197c886167c7ffd370b9fe9daff656b3
  • a739b03a7192828b0da31d077609981bf67912a74470bc19cd7e28c9b44761eb
  • 4eb22da818d15108ceebe699116459a79046716ca695ebc81668c042b7557e2e
  • 6d27525b615b4bfd10284fda160a454b131ed305d39da4fa640d297316a1225d
  • ed9277870a1da0080b7b35f2d6a6b9da931161a9e0e362f2bdbf7456c2f23232
  • 49190fbebc01eaab9551957ff90c5151fe9104e8fc31ac4cf6038dcdaad01f25
  • 86cd8139c074964554c3f674b6f12ec2fe8d8c0765aa7d77117dc099ccf884d8

SHA1

  • c24d8e6e8384f6623ebae9cf35bb6bfeee8cc900
  • b35ee8162ca3666ae14d60634ac3f1a438d2d3b5
  • 25038daa9f2bd4c0da85ca0a491a0e8ee33649f2
  • 8db0f9e9258f7f00861b696c25fa7f7054192eb3
  • 6ebc6d5f99aafd855ada683ff208eaaedffa1b93
  • 6385cf85ba16376a6d22f019ae97194c5eca00a7
  • 2b420bf1a31712098028dcd3651fbef2c66ce802

Remediation

  • Block the threat indicators at respective controls.
  • Avoid downloading attachments from untrusted emails.