Ransom.MSIL.HIDDENTEAR.AL
Trojan-Ransom.HiddenTear(IKARUS); Gen:Variant.Ransom.HiddenTear.3(BITDEFENDER)
Windows
Threat Type: Ransomware
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
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 connects to certain websites to send and receive information. It terminates itself if it detects it is being run in a virtual environment.
It drops files as ransom note.
TECHNICAL DETAILS
17446912 bytes
EXE
Yes
15 Apr 2021
Drops files, Steals information, Connects to URLs/IPs
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:
- %User Temp%\wall.jpg
(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
It drops the following copies of itself into the affected system:
- %User Startup%\HANTA.exe
(Note: %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows 2003(32-bit), XP and 2000(32-bit), or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit), 10(64-bit).)
Autostart Technique
This Ransomware creates the following registry entries to enable automatic execution of dropped component at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
hanta_ransom = "%User Startup%\HANTA.exe"
Other System Modifications
This Ransomware modifies the following registry keys:
HKEY_CURRENT_USER\Control Panel\Desktop
WallpaperStyle = 1
HKEY_CURRENT_USER\Control Panel\Desktop
TileWallpaper = 0
HKEY_CURRENT_USER\Control Panel\Desktop
Wallpaper = %User Temp%\wall.jpg
It sets the system's desktop wallpaper to the following image:
- %User Temp%\wall.jpg
Information Theft
This Ransomware gathers the following data:
- machine GUID
- computer name
- username
Other Details
This Ransomware connects to the following website to send and receive information:
- http://{BLOCKED}gbhdxgb.ueuo.com/current_mirror
It encrypts files with the following extensions:
- .txt
- .doc
- .docx
- .xls
- .xlsx
- .rtf
- .csv
- .ppt
- .pptx
- .odt
- .jpg
- .png
- .csv
- .sql
- .mdb
- .sln
- .php
- .asp
- .aspx
- .html
- .xml
- .psd
- .dat
- .bmp
- .log
- .sq3
- .zip
- .cpp
- .c
- .h
- .htm
- .py
- .py3
- .sqlite
It terminates itself if it detects it is being run in a virtual environment.
It does the following:
- It encrypts .txt files found in network shares
It terminates itself if any of the following file(s) are present:
- SbieDll.dll
It terminates itself if any of the following user name(s) are found in the affected system:
- WALKER
- ARYA
- arya
- walker
- LISA
- Lisa
Ransomware Routine
This Ransomware appends the following extension to the file name of the encrypted files:
- .HANTA
It drops the following file(s) as ransom note:
- %Desktop%\how_to_recover.txt
SOLUTION
9.800
16.658.03
15 Apr 2021
16.659.00
16 Apr 2021
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:
- Troj.Win32.TRX.XXPE50FFF043
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
- hanta_ransom = "%User Startup%\HANTA.exe"
- hanta_ransom = "%User Startup%\HANTA.exe"
Step 6
Restore this modified 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\Control Panel\Desktop
- WallpaperStyle = From 1 to {default}
- WallpaperStyle = From 1 to {default}
- In HKEY_CURRENT_USER\Control Panel\Desktop
- TileWallpaper = From 0 to {default}
- TileWallpaper = From 0 to {default}
- In HKEY_CURRENT_USER\Control Panel\Desktop
- Wallpaper = From %User Temp%\wall.jpg to {default}
- Wallpaper = From %User Temp%\wall.jpg to {default}
Step 7
Search and delete this file
- %User Temp%\wall.jpg
- %Desktop%\how_to_recover.txt
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom.MSIL.HIDDENTEAR.AL. 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 9
Restore encrypted files from backup.
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