Analysis by: Jennifer Gumban
 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

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

It creates registry entries to enable its automatic execution at every system startup.

It connects to a website to send and receive information.

It steals system information.

It terminates itself if it detects it is being run in a virtual environment.

  TECHNICAL DETAILS

Payload: Connects to URLs/IPs, Steals information, Encrypts files

Arrival Details

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

It may be downloaded from the following remote sites:

  • http://{BLOCKED}rwga7em4.onion.link/sec_check.scr
  • {BLOCKED}.{BLOCKED}.0.2

Installation

This Trojan drops a copy of itself in the following folders using different file names:

  • %Application Data%\{random values}

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It drops the following files:

  • {folder of encrypted files}\READ_ME.txt

File Infection

This Trojan searches for target files in the following folders:

  • Pictures
  • Document
  • My Music
  • Desktop
  • My Pictures
  • Personal

Backdoor Routine

This Trojan connects to the following websites to send and receive information:

  • http://{BLOCKED}3cdtvwmy.onion.to/wrap1.php?

    Using the ff. parameters:
       btc={value}
       wid={machine guid}:{system info}:{country}

Information Theft

This Trojan steals system information.

Other Details

This Trojan encrypts files with the following extensions:

  • .mp3
  • .js
  • .txt
  • .doc
  • .docx
  • .xls
  • .xlsx
  • .ppt
  • .pptx
  • odt
  • .jpg
  • .png
  • .csv
  • .sql
  • .mdb
  • .sln
  • .php
  • .asp
  • .aspx
  • .html
  • .xml
  • .psd
  • .pdf

It renames encrypted files using the following names:

  • {original file name}.locked

It terminates itself if it detects it is being run in a virtual environment.

It does the following:

  • Other sites it connects to (non-malicious):

    • https://bitcoin.org/en/getting-started
    • http://aia.startssl.com/certs/ca.crt
    • http://www.download.windowsupdate.com/msdownload/update/v3/static/trustedr/en/authrootseq.txt
    • http://www.download.windowsupdate.com/msdownload/update/v3/static/trustedr/en/authrootstl.cab

  • Checks the country of infected machine using:

    • http://api.hostip.info/country.php

  • Checks the ff system information:

    • SOFTWARE\Microsoft\Windows\CurrentVersion NT
    • SOFTWARE\Microsoft\Cryptography\MachineGuid
    • SOFTWARE\Microsoft\Windows\CurrentVersion\NT ProductName
    • SOFTWARE\Microsoft\Windows\CurrentVersion\NT CSDVersion

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 12.266.05
FIRST VSAPI PATTERN DATE: 11 Jan 2016
VSAPI OPR PATTERN File: 12.267.00
VSAPI OPR PATTERN Date: 12 Jan 2016

Step 1

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

Step 2

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 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Microsoft = "{malware path}\{malware name}"

Step 4

Search and delete these files

[ 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.
  • READ_ME.txt

Step 5

Scan your computer with your Trend Micro product to delete files detected as RANSOM_CRYPZUQUIT.SMA. 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 this Knowledge Base page for more information.

Step 6

Restore encrypted files from backup.


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