Ransom.Win32.STOP.GD
Trojan:Win32/Raccoon.RI!MTB (MICROSOFT), W32/GenKryptik.FBYO!tr (FORTINET)
Windows

Threat Type: Ransomware
Destructiveness: No
Encrypted: No
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
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:
- %System Root%\SystemID\PersonalID.txt
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
It adds the following processes:
- {Malware Path}\{Malware Filename}.exe
- icalcs "%AppDataLocal%\{GUID}" /deny *S-1-1-0:(OI)(CI)(DE,DC)
- %AppDataLocal%\{GUID}\build2.exe
- %AppDataLocal%\{GUID}\build3.exe
- %System%\schtasks.exe /C /create /F /sc minute /mo 1 /tn "Azure-Update-Task" /tr "%Application Data%\Microsoft\Network\mstsca.exe"
(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
It creates the following folders:
- %System Root%\SystemID
- %AppDataLocal%\{GUID}
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Autostart Technique
This Ransomware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
SysHelper = "%AppDataLocal%\{GUID}\{Malware Filename}{Malware Filename}.exe" --AutoStart
Other System Modifications
This Ransomware adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion
SysHelper = 1
Download Routine
This Ransomware connects to the following website(s) to download and execute a malicious file:
- http://{BLOCKED}.{BLOCKED}.2.1/005999801976.zip
- http://{BLOCKED}.{BLOCKED}.2.1/517
- http://{BLOCKED}.top/dl/build2.exe
- http://{BLOCKED}rlights.com/test1/get.php?pid={hash}&first=true
- http://{BLOCKED}rlights.com/files/1/build3.exe
It saves the files it downloads using the following names:
- %AppDataLocal%\{GUID}\build2.exe
- %AppDataLocal%\{GUID}\build3.exe
(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Information Theft
This Ransomware gathers the following data:
- IP Address
- MAC Address
- Computer Name
- User Name
Other Details
This Ransomware connects to the following URL(s) to get the affected system's IP address:
- https://api.2ip.ua/geo.json
- It terminates and deletes itself on the affected system if the return of the IP address location is any of the following:
- RU (Russia)
- BY (Belarus)
- UA (Ukraine)
- AZ (Azerbaijan)
- AM (Armenia)
- TJ (Tajikistan)
- KZ (Kazakhstan)
- KG (Kyrgyzstan)
- UZ (Uzbekistan)
- SY (Syrian Arab Republic)
- It terminates and deletes itself on the affected system if the return of the IP address location is any of the following:
It accepts the following parameters:
- --Admin → runs the malware as admin
- --AutoStart → executes using autorun registry keys
- IsAutoStart/IsNotAutoStart → executes malware as an autostart or not
- IsTask/IsNotTask → executes malware as a task or not
It adds the following scheduled tasks:
- Task Name: Azure-Update-Task
Task Action: %Application Data%\Microsoft\Network\mstsca.exe - Task Name: Time Trigger Task
Task Action: %AppDataLocal%\{GUID}\{Malware Filename}.exe --Task
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
Ransomware Routine
This Ransomware renames encrypted files using the following names:
- {Original Filename}.{Original Extension}.zatp
It drops the following file(s) as ransom note:
- {Encrypted Directory}\_readme.txt
SOLUTION
Step 1
Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:
-
PUA.Win32.TRX.XXPE50FFF062
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
Restart in Safe Mode
Step 5
Delete this registry value
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
- SysHelper = %AppDataLocal%\{GUID}\{Malware Filename}{Malware Filename}.exe --AutoStart
- SysHelper = %AppDataLocal%\{GUID}\{Malware Filename}{Malware Filename}.exe --AutoStart
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion
- SysHelper = 1
- SysHelper = 1
Step 6
Deleting Scheduled Tasks
The following {Task Name} - {Task to be run} listed should be used in the steps identified below:
- Time Trigger Task - %AppDataLocal%\{GUID}\{Malware Filename}.exe --Task
- Azure-Update-Task - %Application Data%\Microsoft\Network\mstsca.exe
For Windows 2000, Windows XP, and Windows Server 2003:
- Open the Windows Scheduled Tasks. Click Start>Programs>Accessories>
System Tools>Scheduled Tasks. - Locate each {Task Name} values listed above in the Name column.
- Right-click on the said file(s) with the aforementioned value.
- Click on Properties. In the Run field, check for the listed {Task to be run}.
- If the strings match the list above, delete the task.
For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012:
- Open the Windows Task Scheduler. To do this:
• On Windows Vista, Windows 7, and Windows Server 2008, click Start, type taskschd.msc in the Search input field, then press Enter.
• On Windows 8, Windows 8.1, and Windows Server 2012, right-click on the lower left corner of the screen, click Run, type taskschd.msc, then press Enter. - In the left panel, click Task Scheduler Library.
- In the upper-middle panel, locate each {Task Name} values listed above in the Name column.
- In the lower-middle panel, click the Actions tab. In the Details column, check for the {Task to be run} string.
- If the said string is found, delete the task.
Step 7
Search and delete this file
- %System Root%\SystemID\PersonalID.txt
- {Encrypted Directory}\_readme.txt
- %AppDataLocal%\{GUID}\build2.exe
- %AppDataLocal%\{GUID}\build3.exe
Step 8
Search and delete these folders
- %System Root%\SystemID
- %AppDataLocal%\{GUID}
Step 9
Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom.Win32.STOP.GD. 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 10
Restore encrypted files from backup.
Step 11
Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.STOP.GD. 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:
Did this description help? Tell us how we did.