Modified by: John Rey Canon
 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It drops files as ransom note.

  TECHNICAL DETAILS

File Size: 632,832 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 28 Oct 2019

Arrival Details

This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Ransomware drops the following files:

  • %All Users Profile%\data1.tmp

(Note: %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). )

Other System Modifications

This Ransomware changes the desktop wallpaper by modifying the following registry entries:

HKCU\Control Panel\Desktop
Wallpaper = %User Temp%\000.bmp

Other Details

This Ransomware does the following:

  • It performs random HTTP request using the format http:://{URL}/{Strings}/{Random String}.{Extensions}
    • URL:
      • {BLOCKED}.114.4
      • {BLOCKED}.114.11
      • {BLOCKED}.114.25
      • {BLOCKED}.114.26
      • {BLOCKED}.114.31
      • {BLOCKED}.114.32
      • {BLOCKED}.114.37
      • {BLOCKED}.114.38
      • {BLOCKED}.114.77
      • {BLOCKED}.114.79
    • Strings:
      • account
      • analytics
      • archive
      • check
      • content
      • create
      • edit
      • forum
      • login
      • logout
      • messages
      • news
      • payout
      • post
      • private
      • register
      • sepa
      • signin
      • signout
      • support
      • task
      • ticket
      • tracker
      • transferout
      • update
      • view
      • webaccess
      • webauth
      • wire
      • withdrawal
    • Extensions:
      • .php
      • .asp
      • .aspx
      • .cgi
      • .jsp
      • .jspx
      • .action
      • .html
      • .phtml
      • .shtml
  • Access the following URL:
    • http://{BLOCKED}.114.37/auth/login

Ransomware Routine

This Ransomware avoids encrypting files with the following strings in their file name:

  • autorun.inf
  • boot.ini
  • desktop.ini
  • ntuser.dat
  • iconcache.db
  • bootsect.bak
  • ntuser.dat.log
  • thumbs.db
  • Bootfont.bin
  • lnk
  • exe
  • sys
  • dll

It avoids encrypting files with the following strings in their file path:

  • :\Windows
  • \Games\
  • \Tor Browser\
  • \ProgramData\
  • \cache2\entries\
  • \Low\Content.IE5\
  • \User Data\Default\Cache\
  • \All Users
  • \IETldCache\
  • \Local Settings\
  • \AppData\Local
  • \Program Files

It appends the following extension to the file name of the encrypted files:

  • {Original FileExtension}.{Random Extension}

It drops the following file(s) as ransom note:

  • {Encrypted Directory}\DECRYPT-FILES.txt

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.458.05
FIRST VSAPI PATTERN DATE: 28 Oct 2019
VSAPI OPR PATTERN File: 15.459.00
VSAPI OPR PATTERN Date: 29 Oct 2019

Step 1

Trend Micro products with the XGen technology detect this malware as

[ Learn More ]

Step 2

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 3

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 4

Identify and terminate files detected as Ransom.Win32.MAZE.B

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 5

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.  
  • %All Users Profile%\data1.tmp
  • %User Temp%\000.bmp
  • {Encrypted Directory}\DECRYPT-FILES.txt

Step 6

Reset your Desktop properties

[ Learn More ]

Step 7

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.MAZE.B. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check the following Trend Micro Support pages for more information:


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