Gomer ransomware: what it is and how to remove it
Gomer ransomware is a file locking virus belonging to the Outsider crypto-malware family and was first spotted by security researcher dnwls0719 in late June 2020. Once inside the system, it encrypts all the pictures, videos, music, MS Office, PDF, and other files with the help of the RSA 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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Gomer ransomware: summary
| Name | Gomer ransomware |
|---|---|
| Type | File locking virus, crypto-malware |
| Family | Outsider ransomware |
| File extension | All personal files are appended with .gomer marker |
| Ransom note | GOMER-README.txt |
| Ransom size | Unknown, although previously crooks asked for 600 Eur in Bitcoin and sometimes Dash cryptocurrency |
| 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 14 more facts
| File decryption | The best way for data recovery is backups. However, if such were not retained, CERT Polska might be able to recover data for free. To contact it, please write an email at cert@cert.pl and attach the ransom note along with a few encrypted files. If that does not help, check for alternative solutions below |
|---|---|
| Detection names | No Microsoft detection name is known |
| Contact | gomer@pm.me, support-gomer@pm.me, cert@cert.pl |
| Encrypted file extension | .gomer |
| 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 | .gomer |
| Attacker contacts | gomer@pm.me |
| Free decryptor | No free decryptor is known (checked 6 October 2026) |
| First seen | 23 June 2020 |
| Facts checked | 6 October 2026 |
- File extension:
.gomer - Note file:
GOMER-README.txt - Contact:
gomer@pm.me
From our report of Jun 2020 · not reviewed since
More from our earlier report on Gomer ransomware
- In some cases, malware can negatively impact the performance of a Windows machine.
- To RESTORE your files, follow this instructions: Gomer service charges a payment for file decryption tool Contact us with attached Gomer-readme.txt Receive Gomer file decryption tool Run the tool and successfully RESTORE all your files!
- Gomer service charges a payment for file decryption tool
- Contact us with attached Gomer-readme.txt
- Receive Gomer file decryption tool
- Run the tool and successfully RESTORE all your files!
The Gomer ransomware note
! ATTENTION !
----------------------------------
! STRICTLY FORBIDDEN TO USE THIRD-PARTY DECRYPTION SOFTWARE - FILES WILL BE LOST !
----------------------------------
Due vulnerability in your system all files have been protected with strong private key to safe them from unathorized access.
To RESTORE your files, follow this instructions:
We guarantee:
100% Successful restoring all of your files
100% Satisfaction guarantee
100% Fast and secure service
As a proof of our trusted service, you can send us 1 file and get it decrypted for free!
----------------------------------
! ONLY ORIGINAL GOMER DECRYPTION TOOL CAN RESTORE YOUR FILES !
----------------------------------
Contacts: support-gomer@pm.me
Payments accepted: Bitcoin (BTC)
ID KEY:
~ GOMER ~
How to remove Gomer 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 Gomer 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
Unplug the network cable or turn off Wi-Fi, and disconnect USB drives, external disks and network shares, so Gomer ransomware 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: 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
Your files now end in
.gomerand the instructions are inGOMER-README.txt. Save both to a USB stick, a copy of the note and two small encrypted files, before anything else.On another device, check them with ID Ransomware or Crypto Sheriff: the family name decides which decryptor, if any, can help. Keep the note's ID and contact line for your report.
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
Our last check found that for Gomer ransomware, 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
Step 4: Remove the ransomware before you restore or decrypt
Removing Gomer ransomware 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 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
Windows keeps shadow copies for restore points and backups, and some ransomware fails to delete them.
vssadmin list shadowsin 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.
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
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 Gomer ransomware 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
- 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.
From our report of Jun 2020 · not reviewed since
Gomer ransomware - data locker that can prevent access to personal files until the ransom in Bitcoin is paid
Gomer ransomware is a file locking virus belonging to the Outsider crypto-malware family and was first spotted by security researcher dnwls0719 in late June 2020.
Once inside the system, it encrypts all the pictures, videos, music, MS Office, PDF, and other files with the help of the RSA encryption algorithm. As a result, victims are unable to access any of the personal data located on the PC. Besides, all the files are marked with .gomer extension and are missing their original icons.
Another sign of the Gomer virus infection comes right after that - a text file called GOMER-README.txt is dropped on users' desktop.
This ransom note explains what happened to the hosts' files and that, allegedly, the only way to recover them is by paying an unknown amount of ransom in Bitcoin for the Gomer ransomware decryption key. However, victims should not contact cybercriminals via the provided gomer@pm.me email, as they might never receive the promised tool.
It is yet not completely known how Gomer ransomware is spread, although cybercriminals typically use multiple attack vectors, including:
Regardless of how the virus accessed your machine, however, the result always remains the same - your data gets encrypted. However, you should not panic and first focus on Gomer ransomware removal that should be achieved with the help of powerful security software, such as or .
The contents of the ransom note are as follows:
There are several claims that the malicious actors behind the Gomer file virus are trying to make. For example, they are the only ones who can restore the encrypted data, although it is not true. They also offer a free decryption service for one file. All these promises are made for victims not to doubt the integrity of these statements and pay the ransom.
It is yet unknown what is is the amount that the attackers are asking for, although the payment is meant to be performed with the help of Bitcoin cryptocurrency.
This is the most preferred method that ransomware developers use, as it allows them to stay anonymous when retrieving the money. In previous versions of Gomer ransomware, threat actors were asking for 600 Euro, although this can vary from victim to victim.
Regardless, security researchers from dieviren.de do not recommend contacting cybercriminals, as they might simply never send you the promised Gomer ransomware decryption tool, and you will end up losing your money for good.
Instead, you should rely on alternative data recovery solutions - there are several options available, as we explain in the recovery section below. However, you should first remove Gomer ransomware from the system, and only then try to restore your files.
For that, you should employ powerful security software and perform a full system scan. You should note that removing the virus will not allow you to open .gomer files, as data encryption and malware infection processes are separate. Thus, do not expect that the anti-malware program will restore your files to the way they were prior to the infection.
However, you should also take care of your Windows computer after the Gomer ransomware is terminated.
- Spam email attachments and hyperlinks
- Exploit kits and software vulnerabilities
- Software cracks and pirated program installers
- Unprotected Remote Desktop (RDP) connections
- Malicious advertisements, etc.
From our report of Jun 2020 · not reviewed since
Ransomware infection methods and prevention steps
As mentioned above, there are several ways how you could have got your computer infected with ransomware, as cybercriminals commonly use several different techniques in order to affect a broader spectrum of victims.
Nonetheless, some strains, such as Djvu, have seen immense success by only using software cracks for the delivery. However, you should equip your computer with comprehensive security solutions and apply adequate measures to prevent ransomware infections in the future.
Once the infection spreads on the PC, files immediately get encrypted. Even if the malware is removed, the encrypted data cannot be opened - this is the main trait that results in such devastating consequences for users, as they might lose their precious photos, school work, and much more.
To protect your machine from ransomware attacks, follow these steps:
- Employ powerful security software and keep it updated;
- Enable Firewall and use ad-block;
- Always patch Windows and the installed software with the latest security updates;
- Protect all your accounts with secure alphanumeric passwords;
- Never download software cracks or pirated program installers.
From our report of Jun 2020 · not reviewed since
Remove Gomer file virus and recover your files without contacting cybercriminals
While many ransomware viruses delete themselves as soon as they finish the encryption process, some leftovers may remain.
Additionally, it can also come along with other infections, so it is important to make sure that Gomer ransomware removal is performed properly.
Although keep in mind that not all anti-malware apps will be able to detect all viruses, as they use different databases. Nonetheless, according to Virus Total, malware is detected by dozens of security applications currently.
Instead, you should use alternative solutions we provide in our recovery section below.
[GI=method-1]In case you are unable to eliminate the virus in normal mode, access Safe Mode as explained below:
[GI=method-2]System Restore can also be used for Gomer file virus elimination:
Recovery software might be able to find working copies of at least some files:
Make use of Windows Previous Versions Feature
This method will only work if you had System Restore enabled before ransomware infection took place.
ShadowExplorer might be able to retrieve all your data
In case ransomware failed to delete Shadow Volume Copies, ShadowExplorer should be able to recover all your data.
Contact CERT Polska for free .gomer file recovery
Write an email at cert@cert.pl and attach ransom note (GOMER-README.txt) along with a few encrypted 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
Gomer ransomware could only hurt the files that had no second copy, and the signs (files that end in .gomer 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.
Stream videos without limitations, no matter where you are
There are multiple parties that could find out almost anything about you by checking your online activity.
While this is highly unlikely, advertisers and tech companies are constantly tracking you online. The first step to privacy should be a secure browser that focuses on tracker reduction to a minimum.
Even if you employ a secure browser, you will not be able to access websites that are restricted due to local government laws or other reasons. In other words, you may not be able to stream Disney+ or US-based Netflix in some countries. To bypass these restrictions, you can employ a powerful VPN, which provides dedicated servers for torrenting and streaming, not slowing you down in the process.
Data backups are important - recover your lost files
Ransomware is one of the biggest threats to personal data.
Once it is executed on a machine, it launches a sophisticated encryption algorithm that locks all your files, although it does not destroy them. The most common misconception is that anti-malware software can return files to their previous states. This is not true, however, and data remains locked after the malicious payload is deleted.
While regular data backups are the only secure method to recover your files after a ransomware attack, tools such as can also be effective and restore at least some of your lost data.
Questions about Gomer ransomware
How do I open .gomer files?
You cannot open them by renaming or with another program, because the content of files ending in .gomer 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 Gomer ransomware decryptor?
We last checked on 6 October 2026, and for Gomer 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 "Gomer 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.
Did Gomer ransomware steal my files or passwords?
We do not know yet. Nothing published so far shows data theft by Gomer ransomware, but the only confirmed sign is files that end in .gomer 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.
How did Gomer ransomware get on my computer?
The way Gomer 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 .gomer 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 Gomer 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.
What does GOMER-README.txt tell me about the ransomware?
Quite a lot. The file name GOMER-README.txt, the wording, the contact addresses and the format of the personal ID are typical for each family. Uploading the note together with one encrypted file to ID Ransomware or No More Ransom's Crypto Sheriff usually names the family within seconds.
That name decides your options: some families have free decryptors, some can be partially recovered, and some cannot be decrypted at all. The note's claims about stolen data should be taken seriously but not at face value.
Will .gomer spread to my other drives?
It can. Ransomware encrypts every drive and network share it can reach while it runs, so external disks, USB sticks and shared folders connected during the attack may also have files ending in .gomer. Disconnect everything now, then check each device from a clean computer.
Do not plug a backup drive into the infected PC until the ransomware has been removed with an offline scan. Cloud folders such as OneDrive sync the encrypted versions, but they keep earlier versions you can usually restore.
Will Fortect remove Gomer 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 Gomer 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
- Wikipedia: RSA (cryptosystem) (read October 6, 2026)
- Dieviren: Dieviren (read October 6, 2026)
- 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)