Ransom.MSIL.CRYPTEAR.A
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 deletes itself after execution.
It encrypts files with specific file extensions. It drops files as ransom note.
TECHNICAL DETAILS
120,320 bytes
EXE
Yes
23 Jul 2019
Connects to URLs/IPs, Displays windows, Displays message/message boxes
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 a copy of itself in the following folders using different file names:
- %System Root%\{username}\Systems\local.exe
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
It creates the following folders:
- %System Root%\{username}\Systems
- %System Root%\{username}
(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
Other System Modifications
This Ransomware adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Systems = "%System Root%\{username}\Decrypter.exe"
Download Routine
This Ransomware connects to the following website(s) to download and execute a malicious file:
- http://{BLOCKED}agy.ru/Decrypter.exe
- http://{BLOCKED}agy.ru/ransom.jpg
It saves the files it downloads using the following names:
- %Desktop%\Decrypter.exe - Ransomware Decrypt screen
- %System Root%\{username}\ransom.jpg - Wallpaper
- %System Root%\{username}\Decrypter.exe - Ransomware Decrypt screen
(Note: %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\Desktop on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)
Other Details
This Ransomware connects to the following URL(s) to check for an Internet connection:
- https://maper.info/XGnV6
It connects to the following website to send and receive information:
- http://{BLOCKED}agy.ru/write.php?computer_name={computer name}&userName={username}&password={15 random characters}&allow=ransom
It deletes itself after execution.
Ransomware Routine
This Ransomware encrypts files with the following extensions:
- .001
- .7-zip
- .ace
- .apk
- .arj
- .asp
- .aspx
- .avi
- .bmp
- .bz2
- .c
- .cab
- .contact
- .core
- .cpp
- .crproj
- .cs
- .csv
- .dat
- .db
- .dll
- .doc
- .docx
- .dwg
- .exe
- .f3d
- .gzip
- .htm
- .html
- .ico
- .iso
- .jar
- .jpg
- .lnk
- .lzh
- .mdb
- .mkv
- .mov
- .mp3
- .mp3
- .mp4
- .mpeg
- .mpg
- .odt
- .pas
- .pdb
- .php
- .png
- .ppt
- .pptx
- .psd
- .py
- .rar
- .rtf
- .settings
- .sln
- .sql
- .tar
- .torrent
- .txt
- .uue
- .xls
- .xlsx
- .xml
- .xz
- .z
- .zip
It renames encrypted files using the following names:
- {encrypted file}.Pox
It drops the following file(s) as ransom note:
- %Desktop%\HOW TO DECRYPT FILES.txt
(Note: %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\Desktop on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)
It leaves text files that serve as ransom notes containing the following text:
NOTES:
Decrypter.exe displays the following window:
SOLUTION
9.850
15.251.00
24 Jul 2019
Step 1
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 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
Identify and terminate files detected as Ransom.MSIL.CRYPTEAR.A
- 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.
- 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.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 4
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.
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- Systems = "%System Root%\{username}\Decrypter.exe"
Step 5
Search and delete this folder
- %System Root%\{username}
- %System Root%\{username}\Systems
Step 6
Search and delete these files
- %Desktop%\Decrypter.exe
- %Desktop%\HOW TO DECRYPT FILES.txt
- %System Root%\{username}\ransom.jpg
- %System Root%\{username}\Decrypter.exe
Step 7
Scan your computer with your Trend Micro product to delete files detected as Ransom.MSIL.CRYPTEAR.A. 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:
Step 8
Reset your Desktop properties
Step 9
Restore encrypted files from backup.
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