Boooom ransomware: what it is and how to remove it
Boooom belongs to a category of malware known as ransomware - one of the most dangerous computer threats around. Once installed on a Windows computer or on a network, it infects the related systems and then begins the encryption process of files using a strong encryption algorithm.
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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Boooom ransomware: summary
| Name | Boooom ransomware |
|---|---|
| Type | Ransomware, data locking malware |
| File extension | .boooom, along with user ID and the contact email |
| Ransom note | decrypt_info.txt |
| Contact | Email monster666@tuta.io or Telegram @Online7_365 |
| File Recovery | If no backups are available, recovering data is almost impossible. Nonetheless, we suggest you try the alternative methods that could help you in some cases – we list them below |
| 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 | .boooom |
| 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 | One write-up by a security site; no sample analysed yet |
| Encrypted files | .boooom |
| Attacker contacts | monster666@tuta.io |
| Free decryptor | No free decryptor is known (checked 6 October 2026) |
| First seen | 8 September 2021 |
| Facts checked | 6 October 2026 |
- File extension:
.boooom - Note file:
decrypt_info.txt - Contact:
monster666@tuta.io
From our report of Sep 2021 · not reviewed since
More from our earlier report on Boooom ransomware
- Perform a full system scan with powerful security software, such as ,
- Malware can seriously tamper with Windows systems, causing errors, crashes, lag, and other stability issues after it is terminated.
- Free Ransomware Decryptors by Kaspersky
The Boooom ransomware note
All your files have been encrypted due to a security problem with your PC. If you want to restore them, write us to the e-mail monster666@tuta.io
or:
write to us in telegram
hxxps://t.me/Online7_365
or:
@Online7_365
Send us this file
decrypt_info
===========================
Free decryption as a guarantee
Before paying, you can send 1-2 files for free decryption. File format: txt doc pdf jpeg jpg gif png bmp Total file size should not exceed 2 MB (without archive)
===========================
You can buy Bitcoins here: hxxps://localbitcoins.com
Or use the search how to buy Bitcoins in your country
===========================
IMPORTANT!!!
Remember that your files are encrypted and only WE can recover them!
Do not try to recover yourself, as well as on third-party resources, you will lose your files and money forever!
How to remove Boooom 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 Boooom 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
Boooom 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
decrypt_info.txtand one or two files ending in.boooomto 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 Boooom 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 Boooom 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.
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 Sep 2021 · not reviewed since
Boooom ransomware asks for Bitcoins in exchange for a decryption key
Boooom belongs to a category of malware known as ransomware - one of the most dangerous computer threats around.
Once installed on a Windows computer or on a network, it infects the related systems and then begins the encryption process of files using a strong encryption algorithm.
During this process, all pictures, documents, videos, and other files are appended with a .[monster666@tuta.io].boooom extension. Modifications can also be noticed by the fact that all personal files are stripped from their original icons, and blank ones are shown instead. Such data becomes no longer readable, which renders it useless for its owners.
In order to decode these files, users are asked to contact cybercriminals behind the attack via monster666@tuta.io email or Telegram (@Online7_365). Note that this contact email is also used within the extension of the locked files and might change in the later versions of the Boooom virus.
All the relevant information is compiled in a file titled decrypt_info.txt, which can be opened on a Notepad or other application. It serves as a note from hackers, who demand to pay Bitcoins in exchange for a decryption tool that allegedly is supposed to decrypt all the data.
However, since this strain is relatively new (it was first spotted in early September 2021) and it is not known who the developers are, there is no guarantee or examples where victims managed to retrieve the required decryption software from the attackers. Hence, we strongly recommend avoiding any contact with the criminals.
Instead, we will explore alternative methods that could hopefully help you restore at least some portion of your data. But before that, there are several important steps that need to be done - check them all below.
It is yet unknown which attack vectors cybercriminals use to spread the virus. According to security experts, there could be many different ways how victims get infected - here are a few examples:
While you can no longer undo the infection of Boooom ransomware, you should take adequate measures to ensure that you don't get infected in the future. For that, be more careful when browsing the web (stop visiting high-risk websites and never download pirated programs), apply all the available software updates, and, most importantly, install a powerful anti-malware tool such as or .
Once the virus manages to get into a Windows machine, the changes happen instantaneously - it includes system and personal files. For example, malware affects the registry, drops many files, launches new processes while shutting down the others, etc.
These changes might sometimes damage the operating system, and security software would not be able to fix it, which might result in crashes, errors, and other issues.
After the infection is complete, users can spot it almost right away - they are not able to open their files anymore, and a ransom note shows up automatically, which reads:
- Spam email attachments of hyperlinks
- Malicious ads and fake updates
- Software cracks, torrents, repacked installers
- Software vulnerabilities, etc.
From our report of Sep 2021 · not reviewed since
Step 1. Disconnect your PC from the internet
Once ransomware finishes its job, it is likely to connect to a remote server for various reasons, e.g., the attackers might send additional modules or updates.
This step is particularly important in the corporate environment, although it seems that this strain mainly targets home users.
The easiest way to disconnect from the internet is by switching it off via the taskbar or by pulling out the ethernet cable. If your computer is connected to a network, follow these steps:
Keep in mind that you should also disconnect from cloud storage services such as OneDrive, as well as external storage devices (USB sticks, external hard drives, etc.).
- Type in Control Panel in Windows search and press Enter
- Go to Network and Internet
- Click Network and Sharing Center
- On the left, pick Change adapter settings
- Right-click on your connection (for example, Ethernet), and select Disable
- Confirm with Yes.
From our report of Sep 2021 · not reviewed since
Step 2. Remove malware
If you are a victim of ransomware, it is important to employ anti-malware software for its removal.
Even if the ransomware self-destructs after encrypting your files, malware might still be present and operating in conjunction with other malicious programs. This could lead to further damage and loss of personal information such as banking credentials and login details.
While most malware can be eradicated in a normal mode, some infections might be more stubborn.
If ransomware is impeding the security tool's function, you can access the Safe Mode environment and perform the scan from there.
Windows 7 / Vista / XP
Windows 10 / Windows 8
After reaching Safe Mode, launch , , or another antivirus, update it with the latest definitions and perform a full system scan to remove malware and all its components from the system.
- Click Start > Shutdown > Restart > OK.
- When your computer becomes active, start pressing the 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.
- Right-click on the Start button and select Settings.
- On the left side of the window, pick Recovery.
- Click Restart now.
- Select Troubleshoot.
- Go to Advanced options.
- Select Startup Settings.
- Click Restart.
- Press 5 or click 5) Enable Safe Mode with Networking.
From our report of Sep 2021 · not reviewed since
Step 3. Backup encrypted files
It goes without saying that the easiest way to restore your files is by using backups.
Unfortunately, most ransomware victims fail to use this precautionary measure, and once the infection has begun, it is too late to save one's files.
You can also use these steps to backup currently encrypted files. This is very important, as, if you proceed with data recovery immediately, you might corrupt it for good (note that ransomware does not corrupt your files but rather puts it behind a sophisticated key, only accessible to cybercriminals).
Security experts are known to work on decryption tools for major ransomware strains. In some cases, flaws within the encryption process can be found or criminals' servers seized by the lay authority agencies. In any case, you could look for decryptors on the following pages, although keep in mind it might take a while until there's a working one made.
- No More Ransom Project
- Free Ransomware Decryption Tools from Emsisoft
From our report of Sep 2021 · not reviewed since
Step 4. Use data recovery software
Data recovery software could help you in some situations (it highly depends on the encryption algorithm used, whether ransomware managed to complete its tasks, etc.).
Therefore, it is impossible to tell whether this method will work for you, although you should definitely try.
Install data recovery software
Finally, you always have a choice to cooperate with the attackers. However, we strongly discourage you from doing so, as you might not only lose your files but also your money. Cybercriminals often ask for large sums for decryption, and even fail to provide the promised tool after the payment is made.
- 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.
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
Boooom ransomware could only hurt the files that had no second copy, and the signs (files that end in .boooom 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.
Choose a proper web browser and improve your safety with a VPN tool
Online spying has got momentum in recent years and people are getting more and more interested in how to protect their privacy online.
One of the basic means to add a layer of security - choose the most private and secure web browser. Although web browsers can't grant full privacy protection and security, some of them are much better at sandboxing, HTTPS upgrading, active content blocking, tracking blocking, phishing protection, and similar privacy-oriented features.
However, if you want true anonymity, we suggest you employ a powerful VPN - it can encrypt all the traffic that comes and goes out of your computer, preventing tracking completely.
Lost your files? Use data recovery software
While some files located on any computer are replaceable or useless, others can be extremely valuable.
Family photos, work documents, school projects - these are types of files that we don't want to lose. Unfortunately, there are many ways how unexpected data loss can occur:
- power cuts
- Blue Screen of Death errors
- hardware failures
- crypto-malware attack
- even accidental deletion
To ensure that all the files remain intact, you should prepare regular data backups. You can choose cloud-based or physical copies you could restore from later in case of a disaster. If your backups were lost as well or you never bothered to prepare any, can be your only hope to retrieve your invaluable files.
Questions about Boooom ransomware
How do I open .boooom files?
You cannot open them by renaming or by choosing another program. The .boooom ending shows that Boooom 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 Boooom ransomware. Store the encrypted files on an external disk until then.
Did Boooom ransomware steal my files or passwords?
We do not know yet. Nothing published so far shows data theft by Boooom ransomware, but the only confirmed sign is files that end in .boooom 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.
How did Boooom ransomware get on my computer?
The way Boooom 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 .boooom 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.
Is there a free Boooom ransomware decryptor?
We last checked on 6 October 2026, and for Boooom 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 "Boooom 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.
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.
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.
Is Boooom 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 .boooom from the file names?
You can try it on a copy, but for real ransomware it will not help. The .boooom 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 decrypt_info.txt?
Reading it is fine if you open it in Notepad. A plain text decrypt_info.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 Boooom 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 Boooom 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
- CISA: StopRansomware (read October 6, 2026)
- No More Ransom (read October 6, 2026)
- FTC: How to recognize, remove and avoid malware (read October 6, 2026)
- Microsoft Learn: Microsoft Defender Offline (read October 6, 2026)
- Microsoft Learn: How Microsoft names malware (read October 6, 2026)