Moonshadow ransomware: what it is and how to remove it
Moonshadow ransomware is the threat that encrypts files using army-grade algorithms. These particular powerful tools allow the virus to alter the original code of the file and then make the file useless.
Facts checked October 6, 2026. Removal steps tested on Windows 11 (26H2) and checked against Microsoft's and the browser makers' current documentation. Sections marked as our earlier report are the original text: they describe the threat as it was then and have not been reviewed since. The 2026 status, the removal steps and the questions are current.
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Moonshadow ransomware: summary
| Name | Moonshadow ransomware |
|---|---|
| Type | Cryptovirus, file-locker |
| File marker | .moonshadow and includes victims' ID and contact email |
| Ransom note | Decryption-Guide.HTA and Decryption-Guide.txt |
| Contact details | developer.110@tutanota.com |
| Decryption | Not possible |
| Removal | Scan the PC with security software to find and remove the malware and anything installed with it. Fortect scans Windows for malware and repairs the system files and settings it damaged. Remove it nowTo use the full-featured product, you have to purchase a license for Fortect. The scan is free. |
Show 12 more facts
| Detection names | No Microsoft detection name is known |
|---|---|
| Encrypted file extension | .moonshadow |
| Decryptor | No free decryptor is known for this variant; check No More Ransom (nomoreransom.org) for updates |
| Distribution | Not recorded in the old report |
| Damage | Not recorded in the old report |
| Symptoms | Files renamed with a new extension and a ransom note left in folders |
| Evidence | 4 write-ups by security sites; no sample analysed yet |
| Encrypted files | .moonshadow |
| Attacker contacts | developer.110@tutanota.com |
| Free decryptor | No free decryptor is known (checked 6 October 2026) |
| First seen | 3 June 2022 |
| Facts checked | 6 October 2026 |
- File extension:
.moonshadow - Note file:
Decryption-Guide.txt - Contact:
developer.110@tutanota.com
From our report of Jun 2022 · not reviewed since
More from our earlier report on Moonshadow ransomware
- Threats best removed using AV tools
- Repair of the damaged system data is possible with
- Free Ransomware Decryptors by Kaspersky
The Moonshadow ransomware note
Your Files Are Has Been Locked
Your Files Has Been Encrypted with cryptography Algorithm
If You Need Your Files And They are Important to You, Dont be shy Send Me an Email
Send Test File + The Key File on Your System (File Exist in C:/ProgramData example : KEY-SE-24r6t523 or RSAKEY.KEY) to Make Sure Your Files Can be Restored
Make an Agreement on Price with me and Pay
Get Decryption Tool + RSA Key AND Instruction For Decryption Process
Attention:
1- Do Not Rename or Modify The Files (You May loose That file)
2- Do Not Try To Use 3rd Party Apps or Recovery Tools ( if You want to do that make an copy from Files and try on them and Waste Your time )
3-Do not Reinstall Operation System(Windows) You may loose the key File and Loose Your Files
4-Do Not Always Trust to Middle mans and negotiators (some of them are good but some of them agree on 4000usd for example and Asked 10000usd From Client) this Was happened
Your Case ID : -
Our Email:developer.110@tutanota.com
How to remove Moonshadow ransomware
Tools you'll need
All of these are free except where noted. Download them on a clean device if the infected PC is offline.
- A USB stick: to keep the ransom note, two or three encrypted files and screenshots off the infected PC.
- Microsoft Defender Offline: built into Windows 11 and Windows 10; scans before Windows starts, so running malware cannot hide.
- Microsoft Safety Scanner: a second, portable scanner with current signatures; each download works for 10 days.
- ID Ransomware: identifies the family from the note and one encrypted file and says whether a decryptor exists.
- No More Ransom: the free decryptors from police and security companies; check it again every few months.
- Fortect (optional): scans Windows for malware and repairs the system files and settings it damaged. The free scan is in the box above.
How to remove Moonshadow ransomware and get your files back
Work in this order.
Disconnecting comes first, removal comes before any restore, and nothing here asks you to contact the attackers.
Step 1: Disconnect the PC and unplug backup drives
Moonshadow ransomware encrypts everything it can reach, including drives and shares you connect later. Cut the network first: cable out, or Wi-Fi off from the taskbar.
Then unplug every USB stick and backup disk and pause cloud sync, so the encrypted versions do not replace your online copies. Do not reconnect any of them until the ransomware is removed from the Windows 11 or Windows 10 PC.
Windows 11: turn off Wi-Fi to take the PC offline. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 2: Save the ransom note and confirm the family
Copy
Decryption-Guide.txtand one or two files ending in.moonshadowto a USB stick, and leave the originals where they are.From another device, upload the note and a sample file to ID Ransomware or No More Ransom's Crypto Sheriff, which name the family from the note, the extension and the file structure.
Write down the contact address and your personal ID from the note, because a decryptor or the police may ask for them.
Warning: Never contact the attackers from the infected Windows 11 or Windows 10 PC.
Windows 11: the ransom note and encrypted files to copy for identification. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 3: Check for a free decryptor
For Moonshadow ransomware, no free decryptor is known (checked 6 October 2026). Search the family name in the No More Ransom decryption tools list and in the free decryptors of Emsisoft, Avast and Kaspersky, because new tools appear years after an attack.
Important: Keep the encrypted files even if nothing works today, and do not pay before every free option is ruled out: payment does not guarantee a working key.
Decryptors run on Windows 11 and Windows 10, but only after the ransomware itself is removed.
Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 4: Remove the ransomware before you restore or decrypt
Restoring or decrypting files while Moonshadow ransomware still runs lets it encrypt them again. Run a Full scan in Windows Security > Virus & threat protection > Scan options, then the Microsoft Defender Antivirus (offline scan).
If the ransomware blocks Windows Security, start Safe Mode with Networking and scan from there. Some families install a password stealer as well, so let both scans finish on Windows 11 or Windows 10.
Windows 11: Windows Security > Virus & threat protection > Scan options. Full procedure with screenshots: Run a Microsoft Defender Offline scan
Step 5: Look for shadow copies of the files
Open Command Prompt as administrator and run
vssadmin list shadows. If it lists copies dated before the attack, right-click a folder with encrypted files in File Explorer, choose Properties > Previous Versions, and open or restore a version from before that date.ShadowExplorer, a free tool, shows the same copies when the tab is empty or hidden. Most current families delete shadow copies, so an empty list is normal, but the check takes two minutes on Windows 11 or Windows 10.
Windows 11: vssadmin list shadows shows whether shadow copies exist. Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files
Step 6: Restore the files from a backup or recover deleted originals
Restore from an external backup, File History or OneDrive's version history, choosing a date before the attack. Connect the backup drive only after the scans are clean, or the ransomware encrypts it too.
If there is no backup, file recovery software can sometimes find the deleted originals, because some ransomware writes an encrypted copy and deletes the original file.
Stop writing to the drive and try recovery on Windows 11 or Windows 10 before new files overwrite the space.
Full procedure with screenshots: Recover deleted files (Recycle Bin, backups, OneDrive) On uGetFix
Instructions for each browser and system
The detailed steps for every browser and system this guide covers. Open the one you use.
Identify ransomware affecting your PC
Restore Windows "hosts" file to its original state
Some ransomware might modify Windows hosts file in order to prevent users from accessing certain websites online. For example, Djvu ransomware variants add dozens of entries containing URLs of security-related websites, such as 2-spyware.com. Each of the entries means that users will not be able to access the listed web addresses and will receive an error instead.
Here's an example of "hosts" file entries that were injected by ransomware:
In order to restore your ability to access all websites without restrictions, you should either delete the file (Windows will automatically recreate it) or remove all the malware-created entries. If you have never touched the "hosts" file before, you should simply delete it by marking it and pressing Shift + Del on your keyboard. For that, navigate to the following location:
C:\\Windows\\System32\\drivers\\etc\\
Manual removal using Safe Mode
Important! →
Manual removal guide might be too complicated for regular computer users. It requires advanced IT knowledge to be performed correctly (if vital system files are removed or damaged, it might result in full Windows compromise), and it also might take hours to complete. Therefore, we highly advise using the automatic method provided above instead.
Step 1. Access Safe Mode with Networking
Manual malware removal should be best performed in the Safe Mode environment.
Windows 7 / Vista / XP
- Click Start > Shutdown > Restart > OK.
- When your computer becomes active, start pressing F8 button (if that does not work, try F2, F12, Del, etc. - it all depends on your motherboard model) multiple times until you see the Advanced Boot Options window.
- Select Safe Mode with Networking from the list.
Windows 10 / Windows 8
- Right-click on Start button and select Settings.
- Scroll down to pick Update & Security.
- On the left side of the window, pick Recovery.
- Now scroll down to find Advanced Startup section.
- Click Restart now.
- Select Troubleshoot.
- Go to Advanced options.
- Select Startup Settings.
- Press Restart.
- Now press 5 or click 5) Enable Safe Mode with Networking.
Step 2. Shut down suspicious processes
Windows Task Manager is a useful tool that shows all the processes running in the background. If malware is running a process, you need to shut it down:
- Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
- Click on More details.
- Scroll down to Background processes section, and look for anything suspicious.
- Right-click and select Open file location.
- Go back to the process, right-click and pick End Task.
- Delete the contents of the malicious folder.
Step 3. Check program Startup
- Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
- Go to Startup tab.
- Right-click on the suspicious program and pick Disable.
Step 4. Delete virus files
Malware-related files can be found in various places within your computer. Here are instructions that could help you find them:
- Type in Disk Cleanup in Windows search and press Enter.
- Select the drive you want to clean (C: is your main drive by default and is likely to be the one that has malicious files in).
- Scroll through the Files to delete list and select the following:
Temporary Internet Files
Downloads
Recycle Bin
Temporary files - Pick Clean up system files.
- You can also look for other malicious files hidden in the following folders (type these entries in Windows Search and press Enter):
%AppData%
%LocalAppData%
%ProgramData%
%WinDir%
After you are finished, reboot the PC in normal mode.
Important steps to take before you begin malware removal
File encryption is one component of a ransomware infection, which may also include credential theft, persistence mechanisms, and lateral movement. However, it is important to understand that malware may perform various changes within a Windows operating system, including persistence, scheduled tasks, registry modifications, and security feature tampering.
IMPORTANT for those without backups! →
If you attempt to use security or recovery software immediately, you might permanently damage your files, and even a working decryptor then would not be able to save them.
Before you proceed with the removal instructions below, you should copy the encrypted files onto a separate medium, such as USB flash drive or SSD, and then disconnect them from your computer. The storage device should remain disconnected after copying to prevent accidental modification or deletion. Encrypted data itself does not contain active malicious code, but only the encrypted files—not executables or scripts—should be transferred.
The instructions below might initially seem overwhelming and complicated, but they are not difficult to understand as long as you follow each step in the appropriate order. This comprehensive free guide will help you to handle the malware removal and data recovery process correctly.
If you have any questions, comments, or are having troubles with following the instructions, please do not hesitate to contact us via the Ask Us section.
IMPORTANT! →
It is vital to eliminate malware infection from the computer fully before starting the data recovery process, otherwise ransomware might re-encrypt retrieved files from backups repeatedly.
Restore files using data recovery software
Since many users do not prepare proper data backups prior to being attacked by ransomware, they might often lose access to their files permanently. Paying criminals is also very risky, as they might not fulfill the promises and never send back the required decryption tool.
While this might sound terrible, not all is lost - data recovery software might be able to help you in some situations (it highly depends on the encryption algorithm used, whether ransomware managed to complete the programmed tasks, etc.). Since there are thousands of different ransomware strains, it is immediately impossible to tell whether third-party software will work for you.
Therefore, we suggest trying regardless of which ransomware attacked your computer. Before you begin, several pointers are important while dealing with this situation:
- Since the encrypted data on your computer might permanently be damaged by security or data recovery software, you should first make backups of it - use a USB flash drive or another storage.
- Only attempt to recover your files using this method after you perform a scan with anti-malware software.
Install data recovery software
- Download .
- Double-click the installer to launch it.
- Follow on-screen instructions to install the software.
- As soon as you press Finish, you can use the app.
- Select Everything or pick individual folders where you want the files to be recovered from.
- Press Next.
- At the bottom, enable Deep scan and pick which Disks you want to be scanned.
- Press Scan and wait till it is complete.
- You can now pick which folders/files to recover - don't forget you also have the option to search by the file name!
- Press Recover to retrieve your files.
Create data backups to avoid file loss in the future
Report the incident to your local authorities
Ransomware is a lucrative, highly illegal business, and authorities are actively targeting ransomware operators. The level of investigation and follow-up depends on the country, the scale of the incident, and whether the attack is linked to known ransomware groups. To increase the likelihood of identifying the culprits, the agencies need information. In many cases, reports are used primarily for intelligence gathering, trend analysis, and victim support rather than immediate identification of attackers.
Therefore, by reporting the crime, you could help stop the cybercriminal activities and catch the threat actors. Reporting does not guarantee investigation or recovery of data, but it contributes to broader efforts to track ransomware campaigns. Make sure you include all the possible details, including how did you notice the attack, when it happened, etc. Relevant details may also include affected systems, ransom demands, cryptocurrency wallet addresses, and any communication with the attackers. Additionally, providing documents such as ransom notes, encrypted files, or malware executables would be beneficial.
Law enforcement agencies typically deal with online fraud and cybercrime, although it depends on where you live. Here is the list of local authority groups that handle incidents like ransomware attacks, sorted by country:
- USA - Internet Crime Complaint Center IC3
- United Kingdom - ActionFraud
- Canada - Canadian Anti-Fraud Centre
- Australia - ScamWatch
- New Zealand - ConsumerProtection
- Germany - Polizei
- France - Ministère de l'Intérieur
If your country is not listed above, you should contact the local police department or communications center.
From our report of Jun 2022 · not reviewed since
Moonshadow ransomware locks data and demands Bitcoin payments for the exchange of an alleged decryption tool
Moonshadow ransomware is the threat that encrypts files using army-grade algorithms.
These particular powerful tools allow the virus to alter the original code of the file and then make the file useless. Locked data appears damaged cannot be opened and receives a marker .moonshadow at the end of the original file name right after the file type extension. This is the purpose for later ransom demands.
Moonshadow ransomware virus creates the unique victims' id, and the contact email also gets included in the appendix, so the simple filename becomes a lengthy line of characters. Once that is done, the virus releases a ransom note file on the system, and the pop-up window shows the money demanding message.
The same text and a message from criminals appear in the Decryption-Guide.txt file that gets placed on the desktop and on other folders containing the Moonshadow file virus-locked data. These messages might be scary enough, so you consider paying the demanded sum. That is not recommended.
From our report of Jun 2022 · not reviewed since
Details on the file-locker virus
Moonshadow ransomware virus is a threat similar to VoidCrypt/ Void ransomware because it is developed by the same creators and criminals.
This is not a positive fact for victims because more advanced threats and more dangerous criminals mean the more difficult removal of the infection.
Victims are always advised not to modify files and avoid renaming those locked files by virus creators. Attempts to decrypt files can cause permanent losses of data, according to the Moonshadow ransomware creators. However, paying criminals and not getting files decrypted can cause permanent money and data loss.
The ransom note that the infection places on the system to scare victims, reads:
Moonshadow ransomware demands payments and claims to have the only decryption tool that is capable of recovering all files that got affected during the encryption. This is a criminal tactic that can also involve test decryption offers or ransom discounts or just saying that you need to write them to negotiate.
This way, creators try to trick you into contacting them via emails or other platforms, so the convincing extortionist makes you believe those claims, and money gets transferred. However, once money is in their wallet, criminals disappear. Do not consider these options.
From our report of Jun 2022 · not reviewed since
Remove the infections
Moonshadow ransomware virus is a dangerous threat that can be distributed using various other vectors, so the infection should be treated as soon as those files get encoded.
You might not receive any other indications of the infection because the ransomware manages to run on the system and lock files silently.
Keeping anti-malware tools, in general, is a great habit because it is possible to avoid malware infections when these applications are running scans more often. The Moonshadow ransomware removal process can seem difficult or impossible, but it is doable. Especially when detection rates show success.
However, you should note that removing the virus is not the same as file recovery or decryption. These are needed steps because the threat can run another encryption on files that are newly restored. Run or and scan the machine for any infections or malicious files.
From our report of Jun 2022 · not reviewed since
Restore affected system data
Victims might not notice, bet the Moonshadow file virus is capable of damaging the machine further than those locked documents or images, or archives.
It injects additional malware into the machine to keep its persistence. Experts note that you should keep clearing the virus until the machine is virus-free and only then rely on file recovery.
Moonshadow ransomware can alter the Windows registry database, damage vital bootup, and other sections, delete or corrupt DLL files, etc. Once a system file is damaged by malware, antivirus software is not capable of doing anything about it, leaving it just the way it is. Consequently, users might experience performance, stability, and usability issues, to the point where a full Windows reinstallation is required.
Therefore, we highly recommend using a one-of-a-kind, patented technology of repair. Not only can it fix virus damage after the infection, but it is also capable of removing malware that has already broken into the system thanks to several engines used by the program.
Besides, the application is also capable of fixing various Windows-related issues that are not caused by malware infections, for example, Blue Screen errors, freezes, registry errors, damaged DLLs, etc.
- Download the application by clicking on the link above
- Click on the ReimageRepair.exe
- If User Account Control (UAC) shows up, select Yes
- Press Install and wait till the program finishes the installation process
- The analysis of your machine will begin immediately
- Once complete, check the results - they will be listed in the Summary
- You can now click on each of the issues and fix them manually
From our report of Jun 2022 · not reviewed since
Try to find a decryptor
Moonshadow ransomware virus is not decryptable and the family it is coming from is known for a while.
These tools take a long time to develop and law enforcement needs to obtain the decryption codes and disrupt operations for the development of universal tools for all the versions. These days ransomware gets more and more advanced.
File encryption is a process that is similar to applying a password to a particular file or folder. However, from a technical point of view, encryption is fundamentally different due to its complexity. By using encryption, threat actors use a unique set of alphanumeric characters as a password that can not easily be deciphered if the process is performed correctly.
There are several algorithms that can be used to lock data (whether for good or bad reasons); for example, AES uses the symmetric method of encryption, meaning that the key used to lock and unlock files is the same.
Unfortunately, it is only accessible to the attackers who hold it on a remote server - they ask for a payment in exchange for it. This simple principle is what allows ransomware authors to prosper in this illegal business.
While many high-profile ransomware strains such as Djvu or Dharma use immaculate encryption methods, there are plenty of failures that can be observed within the code of some novice malware developers. For example, the keys could be stored locally, which would allow users to regain access to their files without paying.
In some cases, ransomware does not even encrypt files due to bugs, although victims might believe the opposite due to the ransom note that shows up right after the infection and data encryption is completed.
Therefore, regardless of which crypto-malware affects your files, you should try to find the relevant decryptor if such exists. Security researchers are in a constant battle against cybercriminals. In some cases, they manage to create a working decryption tool that would allow victims to recover files for free.
Once you have identified which ransomware you are affected by, you should check the following links for a decryptor:
If you can't find a decryptor that works for you, you should try the alternative methods we list below. Additionally, it is worth mentioning that it sometimes takes years for a working decryption tool to be developed, so there are always hopes for the future.
Do not skip on the system scan using or anti-malware tools. This can ensure that the Moonshadow ransomware virus is removed with all the related files and intruders. Besides malicious files, there might be damaged system data, so running a scan with is also recommended. Then you can worry about files that got encrypted.
- No More Ransom Project
- Free Ransomware Decryption Tools from Emsisoft
Report it and recover your files
Report it
Report the attack even if you do not expect the files back: insurers and banks ask for the report number, and police use the contacts in the note to link cases.
- United States
- FBI IC3 · FTC ReportFraud
- United Kingdom
- Report Fraud (formerly Action Fraud) · NCSC
- Australia
- ReportCyber (ASD)
- EU countries
- Europol: national reporting sites
Give the victim ID, the note and the date the files were encrypted. A business that holds personal data may also have to notify its data protection authority, in the EU within 72 hours.
Make the next attack harmless
Moonshadow ransomware could only hurt the files that had no second copy, and the signs (files that end in .moonshadow and no longer open) showed exactly which ones those were.
The 3-2-1 rule fixes that:
- three copies
- two media
- one disconnected
A practical version for a home PC: OneDrive or another cloud backup with version history, plus an external disk that you plug in once a week for File History and then unplug. Test a restore now and then by opening a few files from the backup on another device.
Details, schedules and what not to back up are in our 3-2-1 backup guide for Windows.
Access your website securely from any location
When you work on the domain, site, blog, or different project that requires constant management, content creation, or coding, you may need to connect to the server and content management service more often. The best solution for creating a tighter network could be a dedicated/fixed IP address.
If you make your IP address static and set to your device, you can connect to the CMS from any location and do not create any additional issues for the server or network manager that needs to monitor connections and activities. VPN software providers like can help you with such settings and offer the option to control the online reputation and manage projects easily from any part of the world.
Recover files after data-affecting malware attacks
While much of the data can be accidentally deleted due to various reasons, malware is one of the main culprits that can cause loss of pictures, documents, videos, and other important files.
More serious malware infections lead to significant data loss when your documents, system files, and images get encrypted. In particular, ransomware is is a type of malware that focuses on such functions, so your files become useless without an ability to access them.
Even though there is little to no possibility to recover after file-locking threats, some applications have features for data recovery in the system. In some cases, can also help to recover at least some portion of your data after data-locking virus infection or general cyber infection.
Questions about Moonshadow ransomware
How do I open .moonshadow files?
You cannot open them by renaming or by choosing another program. The .moonshadow ending shows that Moonshadow ransomware encrypted the content, and only the matching key can reverse it. Renaming a file back to .docx or .jpg changes nothing except the icon, and it can confuse a future decryptor, so leave the names as they are.
To get the content back, use a backup, an unencrypted copy elsewhere, or a decryptor listed on No More Ransom if one exists for Moonshadow ransomware. Store the encrypted files on an external disk until then.
How did Moonshadow ransomware get on my computer?
The way Moonshadow ransomware spreads has not been documented yet, so look at your own recent activity. On home PCs, ransomware most often comes with cracked programs, game cheats, key generators and fake updates, or with an e-mail attachment that was opened. On business networks, attackers usually log in through Remote Desktop with a stolen or guessed password.
Think back to what was downloaded or installed in the days before files that end in .moonshadow and no longer open, and check the Downloads folder and Installed apps sorted by date. Keep anything suspicious for your report, but do not run it again.
Should I pay the ransom?
We advise against it, and so do the FBI, Europol and national cyber agencies. Payment does not guarantee a working tool: some attackers never reply, some tools damage files, and some variants have no decryptor at all. Paying also funds further attacks and can make you a target again.
Before considering payment, try every recovery option in this guide and report the attack. Companies must involve their legal adviser and insurer, because payments to sanctioned groups can be illegal. If files are truly irreplaceable, store the encrypted copies and wait; decryptors sometimes appear later.
Is there a free Moonshadow ransomware decryptor?
We last checked on 6 October 2026, and for Moonshadow ransomware no free decryptor is known. We check No More Ransom, which collects free tools from police and security companies, and the decryptor pages of the major antivirus vendors. A working decryptor exists only when the encryption has a flaw or the keys were leaked or seized.
Ignore sites and videos that offer a "Moonshadow ransomware decryptor" for download or for a fee: these are usually scams or malware. Real decryptors are free and come from known security companies or law enforcement. Keep the encrypted files in case a tool appears later.
Can a data-recovery company decrypt my files for a fee?
Only if a decryptor already exists or the company pays the attackers for you. Some "ransomware recovery" services advertise that they can decrypt families with no known flaw; in practice they negotiate with the attackers and add their own fee. Others use the same free tools listed on No More Ransom.
Before you hire anyone, ask in writing how they will recover the files, whether they will contact the attackers and what happens if they fail. A legitimate service answers clearly. If a free decryptor exists for your family, you can run it yourself.
Did Moonshadow ransomware steal my files or passwords?
We do not know yet. Nothing published so far shows data theft by Moonshadow ransomware, but the only confirmed sign is files that end in .moonshadow and no longer open, which says nothing about what happened before. Many current ransomware attacks copy files or run a password stealer first, so it is wise to act as if they did.
From a clean device, change the passwords that were saved in the browsers on this PC, starting with e-mail and banking, sign out of all sessions and turn on two-step verification. Watch bank statements and account activity for the next few weeks.
Is Moonshadow ransomware the same as other ransomware with a similar name?
Not necessarily. Ransomware names come from the file extension, the note or a word in the code, so unrelated families often end up with similar names, and one family can appear under several names. The difference matters: a decryptor or advice for one family does not fit another and can damage files.
Compare the ending added to your files and the exact name of the note with the summary table at the top of this guide, then upload the note and one encrypted file to ID Ransomware from a clean device. If the result names another family, follow the guide for that family instead.
Can I just remove .moonshadow from the file names?
You can try it on a copy, but for real ransomware it will not help. The .moonshadow extension is only a label; the file content has been scrambled with a key the attackers hold.
If a renamed copy opens normally, the malware only renamed files, which happens with some fake ransomware, and you can rename the rest back. If it does not open, leave the files as they are. Renaming encrypted files can confuse a decryptor later, so always work on copies.
Should I open Decryption-Guide.txt?
Reading it is fine if you open it in Notepad. A plain text Decryption-Guide.txt cannot harm the PC. Be careful with notes in HTA or HTML format: double-clicking those runs them in a window that can contain scripts, so right-click and choose Open with > Notepad instead.
The note tells you the contact addresses, the claimed amount and the deadline. Do not visit links or write to the addresses from this PC. Use the note to identify the family and check for a free decryptor first.
Will Fortect remove Moonshadow ransomware?
Fortect scans Windows for malware and unwanted programs and repairs the system files and settings they change, and its free scan shows what it finds on your PC before you decide anything.
For Moonshadow ransomware, follow the plan above as well: the browser steps take back permissions and settings that no scanner treats as a threat, and uninstalling the program that brought it removes the source.
Run Microsoft Defender's full scan and, if anything was found, its offline scan as a second opinion. If the symptoms are gone after the plan and both scans are clean, there is nothing more to do.
Sources
- Zscaler: What Is Double Extortion Ransomware? (read October 6, 2026)
- VirusTotal: Virus sample (read October 6, 2026)
- Lesvirus: Lesvirus (read October 6, 2026)
- CISA: StopRansomware (read October 6, 2026)
- No More Ransom (read October 6, 2026)