Heimdall ransomware virus: what it is and how to remove it

Heimdall virus happens to be one of those cyber threats inspired by mythology. The crooks favor Norse mythology after continuously terrorizing the world with the family of ODIN, Locky, and Thor.

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.

Automatic

Get a free scan and check if your PC is infected.

Fortect finds malware, unwanted programs and the Windows damage they leave behind, and repairs it in one pass.

Make sure nothing will rename more files to .heimdall: an automatic scan checks the PC first.

Remove it nowTo use the full-featured product, you have to purchase a license for Fortect. The scan is free.

Do it yourself · free Remove Heimdall ransomware virus yourself 6 steps, about 18 minutes, no software needed.

Start the steps
Heimdall ransomware virus: heimdall
Heimdall ransomware virus as our 2016 report showed it.

Heimdall ransomware virus: summary

Detection namesNo Microsoft detection name is known
Ransom noteNot recorded in our earlier report
Contactemail@email.com
Encrypted file extension.heimdall
DecryptorNo free decryptor is known for this variant; check No More Ransom (nomoreransom.org) for updates
DistributionNot recorded in the old report
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 9 more facts
DamageNot recorded in the old report
NameHeimdall ransomware virus
TypeFile-encrypting ransomware
SymptomsFiles renamed with a new extension
EvidenceOne write-up by a security site; details still limited
Encrypted files.heimdall
Free decryptorNo free decryptor is known (checked 6 October 2026)
First seen17 November 2016
Facts checked6 October 2026

What to search your PC and browser for

  • File extension: .heimdall

How Heimdall ransomware virus behaves

From our report of Nov 2016 · not reviewed since

The effects of Heimdall ransomware

Heimdall virus happens to be one of those cyber threats inspired by mythology.

The crooks favor Norse mythology after continuously terrorizing the world with the family of ODIN, Locky, and Thor. This time they borrowed the name of Heimdall – the deity of dawn and light – for their ransomware image. The virus received more attention after its author published it in GitHub, open-source project network.

There, he demonstrated its features. Though the ransomware is not expected to be released on the massive scale, there are already cases when some users were attacked by this virus. If this malware has befallen you as well, you need to remove Heimdall completely. More information about its elimination steps can be found below the article.

The ransomware has been created using PHP programming language. Though it differs in operation ways, the main principle is the same. Heimdall ransomware hides in a 482-line PHP file. Speaking of encryption techniques, it uses a specific variant of AES-128-CBS algorithm to encode personal data.

Once the file-encrypting virus lands on a system, the file generates a graphical image of the ransom note. It presents email@email.com address as a distinctive label. The price of two bitcoins are asked in exchange for their files. The window also contains the tabs where "password for encrypted" and "password for decrypted" can be entered.

Interestingly, the ransomware places its script in $_SERVER['DOCUMENT_ROOT'] and encrypts the files in this folder. The most destructive feature of this ransomware is that all files, regardless of their format might be corrupted, by the ransomware. Later on, you can identify the locked files by .heimdall extension.

In this regard, the ransomware might be even more damaging than Locky which targets a wide range of files but not all. However, this ransomware suggests that the author might not be related with the crooks of the previously mentioned Locky. The ransom message itself differs from the ransom messages shown by the latter infection.

Though the developer created the ransomware for educational purposes, such behavior of publicly demonstrating the essential features might turn out negatively. There was the case with some variant of Apocalypse when the crook boasted about his creation on the darknet.

However, such boasting was quickly spotted by famous virus researcher Fabian Wosar. After all, the ransomware was quickly taken down. Thus, .heimdall file extension virus also presents the signs of such amateur behavior which is opposed to the refined image of Locky.

Specialists conclude that now, when the virus was presented as the project on GitHub, the chances of it becoming a global ransomware are low. However, there is a risk for other hackers to get some valuable knowledge for future cyber infections. Likewise, it is crucial how quickly you can initiate Heimdall removal. Employ to ensure complete eradication.

Heimdall ransomware virus: heimdall
Heimdall ransomware virus in our 2016 report.

From our report of Nov 2016 · not reviewed since

When does the virus hijack PCs?

Though the Brazilian developer of the hacker was asked to remove the ransomware from GitHub, the malware is still there.

It means that Heimdall malware might not have been set free to roam on the world wide web yet. Nonetheless, when it comes to ransomware and their creators, it is naive to expect any drop of conscience. Even if the author does not deploy massive Heimdall hijack campaign, others might do it for him.

However, now as the virus researchers get a hold of such virus, the ransomware might fail to reach its full destructive power. If it is published on the Internet, be careful not to carelessly open spam messages. They often happen to hide malicious .doc, .js, or .dll binaries containing the file-encrypting malware.

How to remove Heimdall ransomware virus

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 Heimdall ransomware virus 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.

  1. Step 1: Disconnect the PC and unplug backup drives

    Unplug the network cable or turn off Wi-Fi, and disconnect USB drives, external disks and network shares, so Heimdall ransomware virus cannot reach more files. Pause OneDrive, Google Drive or Dropbox sync, because synced folders upload the encrypted copies over the good ones.

    Leave the PC on but offline while you read the next steps, since a restart can let the ransomware run again. This applies to Windows 11 and Windows 10 alike.

    Windows 11 quick settings with Wi-Fi turned off
    Windows 11: turn off Wi-Fi to take the PC offline.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  2. Step 2: Save the ransom note and identify the family

    The name of the family decides whether a free decryptor can help. Copy the ransom note and two small encrypted files to a USB stick, and check them on another device with ID Ransomware or Crypto Sheriff.

    Note the extension added to the files, the contact address and the victim ID shown in the note. Keep the originals on the Windows 11 or Windows 10 PC untouched.

    A ransom note text file next to encrypted files in File Explorer
    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

  3. Step 3: Check for a free decryptor

    Our last check found that for Heimdall ransomware virus, no free decryptor is known (checked 6 October 2026). Look again yourself in the No More Ransom list and the free decryptor pages of Emsisoft, Avast and Kaspersky, which add new families every year.

    A decryptor needs the ransomware gone first, or it encrypts the files again. Keep at least one copy of the encrypted files on an external drive, even if no tool works yet.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  4. Step 4: Remove the ransomware before you restore or decrypt

    Removing Heimdall ransomware virus does not bring the files back, but it has to come first. Start with Defender's Full scan, then the offline scan from the same Scan options page, which checks the disk before Windows loads.

    If the scan cannot start, use Safe Mode with Networking. Delete the ransom notes only after you have saved a copy, because removal tools sometimes leave them behind on Windows 11 and Windows 10.

    Windows Security Scan options with Microsoft Defender Antivirus offline scan selected
    Windows 11: Windows Security > Virus & threat protection > Scan options.

    Full procedure with screenshots: Run a Microsoft Defender Offline scan

  5. Step 5: Look for shadow copies of the files

    Windows keeps shadow copies for restore points and backups, and some ransomware fails to delete them. vssadmin list shadows in an administrator Command Prompt tells you at once whether any exist.

    If they do, right-click the folder that held your files, open Properties > Previous Versions, select a version from before the attack, and click Open to check it before you Restore or copy the files out. Windows 11 and Windows 10 both have the tab.

    Command Prompt running vssadmin list shadows
    Windows 11: vssadmin list shadows shows whether shadow copies exist.

    Full procedure with screenshots: Ransomware: first steps, finding a decryptor and recovering files

  6. Step 6: Restore the files from a backup or recover deleted originals

    A backup made before the attack is the surest way back. Connect it only once the PC is clean, then restore from File History, Windows Backup, OneDrive's Restore your OneDrive or your own external copies.

    Without a backup, try file recovery: the originals that Heimdall ransomware virus deleted may still be on the disk until something overwrites them. Install nothing new on the drive you want to recover from on the Windows 11 or Windows 10 PC.

    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.

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

  1. Click Start > Shutdown > Restart > OK.
  2. 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.
  3. Select Safe Mode with Networking from the list.Windows 7/XP

Windows 10 / Windows 8

  1. Right-click on Start button and select Settings.
    Settings
  2. Scroll down to pick Update & Security.
    Update and security
  3. On the left side of the window, pick Recovery.
  4. Now scroll down to find Advanced Startup section.
  5. Click Restart now.
    Reboot
  6. Select Troubleshoot.Choose an option
  7. Go to Advanced options.Advanced options
  8. Select Startup Settings.Startup settings
  9. Press Restart.
  10. Now press 5 or click 5) Enable Safe Mode with Networking.Enable safe mode

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:

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Click on More details.
    Open task manager
  3. Scroll down to Background processes section, and look for anything suspicious.
  4. Right-click and select Open file location.
    Open file location
  5. Go back to the process, right-click and pick End Task.
    End task
  6. Delete the contents of the malicious folder.

Step 3. Check program Startup

  1. Press Ctrl + Shift + Esc on your keyboard to open Windows Task Manager.
  2. Go to Startup tab.
  3. Right-click on the suspicious program and pick Disable.
    Startup

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:

  1. Type in Disk Cleanup in Windows search and press Enter.
    Disk cleanup
  2. 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).
  3. Scroll through the Files to delete list and select the following: Temporary Internet Files
    Downloads
    Recycle Bin
    Temporary files
  4. Pick Clean up system files.
    Delete temp files
  5. 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.

From our report of Nov 2016 · not reviewed since

Easy Heimdall removal guide

This application deals with ransomware-type viruses effectively and ensures that all elements are completely eradicated.

The security tool will remove Heimdall within a moment. Do not forget to update it. If you somehow find difficulties eliminating the threat, take a look at the below guidelines. After implementing the steps, you should be able to proceed with Heimdall removal.

The best way to decode the files is to employ a backup or original decrypter, but in the absence of them, you can install this utility as it may help you retrieve the files.

This software is another alternative that can help you restore valuable files encrypted by Heimdall ransomware.

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

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.

Backups: the 3-2-1 rule

Keep three copies of files that matter, on two kinds of storage, with one copy offline or off-site.

A disk that stays plugged in is reached by malware like Heimdall ransomware virus together with the PC; one you connect only for the backup is not.

On Windows 11, File History keeps versions on an external drive, and OneDrive keeps earlier versions of synced files. Before restoring anything, make sure the PC no longer shows files that end in .heimdall and no longer open.

Setting it up step by step: 3-2-1 backups on Windows 11 and 10.

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 Heimdall ransomware virus

How do I open .heimdall files?

You cannot open them by renaming or with another program, because the content of files ending in .heimdall has been encrypted. The only ways back are a working decryptor for the family, or clean copies from elsewhere:

  • OneDrive versions
  • File History
  • an offline backup drive
  • Previous Versions if the ransomware did not delete them

Identify the family first by uploading the ransom note and one encrypted file to ID Ransomware or No More Ransom. Avoid websites and programs that promise to open any encrypted file; they do not work and some are scams.

Is there a free Heimdall ransomware virus decryptor?

We last checked on 6 October 2026, and for Heimdall ransomware virus 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 "Heimdall ransomware virus 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.

How did Heimdall ransomware virus get on my computer?

The way Heimdall ransomware virus 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 .heimdall 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.

Did Heimdall ransomware virus steal my files or passwords?

We do not know yet. Nothing published so far shows data theft by Heimdall ransomware virus, but the only confirmed sign is files that end in .heimdall 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.

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 Heimdall ransomware virus 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.

My files got .heimdall overnight. What happened?

Ransomware often runs at night or when the PC is idle, so the encryption finishes before anyone notices. It usually entered earlier through a cracked program, a fake installer, an e-mail attachment or remote desktop with a weak password.

The .heimdall extension marks every file it reached. Start by disconnecting the PC from the network, then identify the family from the ransom note and one encrypted file, check for a decryptor, and look for copies in backups and OneDrive before you consider anything else.

Will removing Heimdall ransomware virus unlock my .heimdall files?

No. Removing Heimdall ransomware virus stops it from encrypting more files and from starting again, but it does not decrypt the files that already end in .heimdall. The scanner does not have the attackers' key.

Files come back only from a backup, from copies the ransomware did not reach, such as OneDrive version history, Previous Versions, e-mail attachments or a phone, or with a working decryptor if one exists.

Remove the ransomware first anyway: if you restore files while it is still active, it can encrypt them again. Keep the encrypted files; a decryptor may be published later.

Will Fortect remove Heimdall ransomware virus?

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 Heimdall ransomware virus, 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

  1. CISA: StopRansomware (read October 6, 2026)
  2. No More Ransom (read October 6, 2026)
  3. FTC: How to recognize, remove and avoid malware (read October 6, 2026)
  4. Microsoft Learn: Microsoft Defender Offline (read October 6, 2026)
  5. Microsoft Learn: How Microsoft names malware (read October 6, 2026)

More removal guides

Questions and experiences: Heimdall ransomware virus

Still seeing it, or found something we did not cover? Ask here: members and our editors answer. Reading is open; writing needs a free account.

0 comments

…

5,493 members already hereReading, writing, commenting and voting. 0 verified · 218 joined this year