The article presents detailed information about Karl virus as well as a step-by-step guide on how to remove associated malicious files from the infected system and how to potentially recover .karl encrypted files.
The name Karl virus is given to a vicious crypto infection that is part of the infamous STOP ransomware family. This ransomware infection aims to disrupt system security so it can unnoticeably reach personal files and encode them with the help of two strong cipher algorithms. To make encrypted files more recognizable Karl virus appends the suffix .karl to their names. When Karl virus reaches its final attack stage, it drops a ransom message file named _readnme.txt and attempts to blackmail you into paying ransom to hackers. According to this message hackers demand a ransom of $490 for the first 72 hours or $980 after this period. It should be paid in cryptocurrency like (Bitcoin, Monero, Dash, etc.) Beware that the completion of this step does not guarantee the successful recovery of your .karl files.
.Karl file infection Summary
|Short Description||A version of the STOP/DJVU ransomware that is designed to encrypt valuable files stored on infected computers and then extort a ransom from victims.|
|Symptoms||Important files are encrypted and renamed with the extension .karl
A ransom message forces victims to contact hackers in order to receive instructions on how to pay a ransom ($490 – $980).
|Distribution Method||Spam Emails; Email Attachments; Corrupted Websites; Software Installers|
See If Your System Has Been Affected by malware
Malware Removal Tool
|User Experience||Join Our Forum to Discuss Karl.|
|Data Recovery Tool||Windows Data Recovery by Stellar Phoenix Notice! This product scans your drive sectors to recover lost files and it may not recover 100% of the encrypted files, but only few of them, depending on the situation and whether or not you have reformatted your drive.|
Karl Virus (STOP Ransomware) – More About the Infection
According to the latest infromation shared by security researchers the so-called Karl virus is a malicious software based on the popular STOP ransomware. Usually spam emails, malicious email attachments, hacked web pages, corrupted freeware installers, and fake software installersFor are used for the spread of threats like STOP Karl ransomware.
The emails that deliver malicious code represent a technique called malspam. The technique appears to be the most convenient way for the spread of ransomware on a large scale. So hackers often bet on it. Hence, it is very likely that virus is mainly delivered via malspam. The malicious code of this new STOP ransomware strain may have landed on your computer after a download of a file that was attached to a legitimate-like email message. Emails that contain malicious files usually attempt to convince you that the attached files contain important information. Hence, they present the files as:
- Invoices coming from reputable sites, like PayPal, eBay, etc.
- Documents from that appear to be sent from your bank.
- An online order confirmation note.
- Receipt for a purchase.
When the infected file is opened on a target device, it triggers Karl ransomware virus and sets the beginning of the attack. At first, the ransomware creates several additional malicious files and places them in folders like %AppData% and %LocalAppData%. With the help of these malicious files Karl ransomware interferes with essential system settings. If it manages to complete all initial infection stages, it will reach target files and modify their code with the help of two strong cipher algorithms.
The encryption phase is realized after the activation of a built-in cipher module. This module scans certain folders that are most likely to be used for the storage of personal files. When it detects a target file it applies changes to its original code. As a result, the encrypted file remains inaccessible until its code is revered back to the original state. In addition, it appears with the suffix .karl at the end of the name.
Unfortunately, Karl virus is likely to corrupt all files that are likely to store valuable information such as:
- Audio files
- Video files
- Document files
- Image files
- Backup files
- Banking credentials, etc
In fact, the purpose of Karl ransomware virus is to blackmail you into paying a ransom fee to hackers. That’s why when it completes all infections stages, it drops a ransom message with instructions on how to continue with a ransom payment process.
Here is a copy of Karl ransomware ransom message which is named _readme.txt:
Don’t worry, you can return all your files!
All your files like photos, databases, documents and other important are encrypted with strongest encryption and unique key.
The only method of recovering files is to purchase decrypt tool and unique key for you.
This software will decrypt all your encrypted files.
What guarantees you have?
You can send one of your encrypted file from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. File must not contain valuable information.
You can get and look video overview decrypt tool:
Price of private key and decrypt software is $980.
Discount 50% available if you contact us first 72 hours, that’s price for you is $490.
Please note that you’ll never restore your data without payment.
Check your e-mail “Spam” or “Junk” folder if you don’t get answer more than 6 hours.
To get this software you need write on our e-mail:
Reserve e-mail address to contact us:
Our Telegram account:
Your personal ID:
You should NOT under any circumstances pay any ransom sum to cybercriminals. This action does not guarantee the recovery of your .karl files.
How to Remove Karl Virus
The so-called Karl virus is a threat with a highly complex code that disrupts system security in order to encrypt personal files. Hence the infected system could be used in a secure manner again only after the complete removal of all malicious files and objects created by Karl ransomware. That’s why it is recommendable that all steps presented in the Karl virus removal guide below should be completed. Beware that the manual ransomware removal is suitable for more experienced computer users. If you don’t feel comfortable with the manual steps navigate to the automatic part of the guide.
How to Recover .karl Files
There are several alternative methods that may be efficient for the recovery of .karl files. You could find them listed under Step 5 from our Karl ransomware removal guide. Beware that you should make copies of all encrypted files and save them on a flash drive for example. This additional step will prevent the permanent loss of encrypted .karl files.
Fix Computer Infected by Karl Ransomware
- Guide 1: How to Remove Karl from Windows.
- Guide 2: Get rid of Karl on Mac OS X.
- Guide 3: Remove Karl in Google Chrome.
- Guide 4: Erase Karl from Mozilla Firefox.
- Guide 5: Uninstall Karl from Microsoft Edge.
- Guide 6: Remove Karl from Safari.
- Guide 7: Eliminate Karl from Internet Explorer.
- Guide 8: Disable Karl Push Notifications in Your Browsers.
About the Karl Research
The content we publish on SensorsTechForum.com, this Karl how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific, adware-related problem, and restore your browser and computer system.
How did we conduct the research on Karl?
Please note that our research is based on independent investigation. We are in contact with independent security researchers, thanks to which we receive daily updates on the latest malware, adware, and browser hijacker definitions.
Furthermore, the research behind the Karl threat is backed with VirusTotal https://www.virustotal.com/gui/home/upload.
To better understand this online threat, please refer to the following articles which provide knowledgeable details.
1.Browser Redirect – What Is It?
2.Adware Is Malicious, and It Uses Advanced Techniques to Infect
3.The Thin Red Line Between Potentially Unwanted Programs and Malware
4.The Pay-Per-Install Affiliate Business – Making Millions out of Adware
5.Malicious Firefox Extensions Installed by 455,000 Users Blocked Updates
How to Remove Karl from Windows.
Step 1: Boot Your PC In Safe Mode to isolate and remove Karl
Step 2: Uninstall Karl and related software from Windows
Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it.
Step 3: Clean any registries, created by Karl on your computer.
The usually targeted registries of Windows machines are the following:
You can access them by opening the Windows registry editor and deleting any values, created by Karl there. This can happen by following the steps underneath:
1. Open the Run Window again, type "regedit" and click OK.
2. When you open it, you can freely navigate to the Run and RunOnce keys, whose locations are shown above.
3. You can remove the value of the virus by right-clicking on it and removing it.
Step 4: Scan for Karl with SpyHunter Anti-Malware Tool
1. Click on the "Download" button to proceed to SpyHunter's download page.
2. After you have installed SpyHunter, wait for it to update automatically.
3. After the update process has finished, click on the 'Malware/PC Scan' tab. A new window will appear. Click on 'Start Scan'.
4. After SpyHunter has finished scanning your PC for any files of the associated threat and found them, you can try to get them removed automatically and permanently by clicking on the 'Next' button.
Video Removal Guide for Karl (Windows).
Get rid of Karl from Mac OS X.
Step 1: Uninstall Karl and remove related files and objects
1.Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:
2. Find Activity Monitor and double-click it:
3.In the Activity Monitor look for any suspicious processes, belonging or related to Karl:
4.Click on the "Go" button again, but this time select Applications. Another way is with the ⇧+⌘+A buttons.
5.In the Applications menu, look for any suspicious app or an app with a name, similar or identical to Karl. If you find it, right-click on the app and select “Move to Trash”.
6: Select Accounts, after which click on the Login Items preference.
Your Mac will then show you a list of items that start automatically when you log in. Look for any suspicious apps identical or similar to Karl. Check the app you want to stop from running automatically and then select on the Minus (“-“) icon to hide it.
7: Remove any left-over files that might be related to this threat manually by following the sub-steps below:
- Go to Finder.
- In the search bar type the name of the app that you want to remove.
- Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
- If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.
In case you cannot remove Karl via Step 1 above:
In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:
1: Click on "Go" and Then "Go to Folder" as shown underneath:
2: Type in "/Library/LauchAgents/" and click Ok:
3: Delete all of the virus files that have similar or the same name as Karl. If you believe there is no such file, do not delete anything.
You can repeat the same procedure with the following other Library directories:
Tip: ~ is there on purpose, because it leads to more LaunchAgents.
Step 2: Scan for and remove Karl files from your Mac
When you are facing problems on your Mac as a result of unwanted scripts and programs such as Karl, the recommended way of eliminating the threat is by using an anti-malware program. SpyHunter for Mac offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.
Video Removal Guide for Karl (Mac)
Remove Karl from Google Chrome.
Step 1: Start Google Chrome and open the drop menu
Step 2:Move the cursor over "Tools" and then from the extended menu choose "Extensions"
Step 3: From the opened "Extensions" menu locate the unwanted extension and click on its "Remove" button.
Step 4: After the extension is removed, restart Google Chrome by closing it from the red "X" button at the top right corner and start it again.
Erase Karl from Mozilla Firefox.
Step 1: Start Mozilla Firefox. Open the menu window
Step 2: Select the "Add-ons" icon from the menu.
Step 3: Select the unwanted extension and click "Remove"
Step 4: After the extension is removed, restart Mozilla Firefox by closing it from the red "X" button at the top right corner and start it again.
Uninstall Karl from Microsoft Edge.
Step 1: Start Edge browser.
Step 2: Open the drop menu by clicking on the icon at the top right corner.
Step 3: From the drop menu select "Extensions".
Step 4: Choose the suspected malicious extension you want to remove and then click on the gear icon.
Step 5: Remove the malicious extension by scrolling down and then clicking on Uninstall.
Remove Karl from Safari.
Step 1: Start the Safari app.
Step 2: After hovering your mouse cursor to the top of the screen, click on the Safari text to open its drop down menu.
Step 3: From the menu, click on "Preferences".
Step 4: After that, select the 'Extensions' Tab.
Step 5: Click once on the extension you want to remove.
Step 6: Click 'Uninstall'.
A pop-up window will appear asking for confirmation to uninstall the extension. Select 'Uninstall' again, and the Karl will be removed.
Eliminate Karl from Internet Explorer.
Step 1: Start Internet Explorer.
Step 2: Click on the gear icon labeled 'Tools' to open the drop menu and select 'Manage Add-ons'
Step 3: In the 'Manage Add-ons' window.
Step 4: Select the extension you want to remove and then click 'Disable'. A pop-up window will appear to inform you that you are about to disable the selected extension, and some more add-ons might be disabled as well. Leave all the boxes checked, and click 'Disable'.
Step 5: After the unwanted extension has been removed, restart Internet Explorer by closing it from the red 'X' button located at the top right corner and start it again.
Remove Push Notifications caused by Karl from Your Browsers.
Turn Off Push Notifications from Google Chrome
To disable any Push Notices from Google Chrome browser, please follow the steps below:
Step 1: Go to Settings in Chrome.
Step 2: In Settings, select “Advanced Settings”:
Step 3: Click “Content Settings”:
Step 4: Open “Notifications”:
Step 5: Click the three dots and choose Block, Edit or Remove options:
Remove Push Notifications on Firefox
Step 1: Go to Firefox Options.
Step 2: Go to “Settings”, type “notifications” in the search bar and click "Settings":
Step 3: Click “Remove” on any site you wish notifications gone and click “Save Changes”
Stop Push Notifications on Opera
Step 1: In Opera, press ALT+P to go to Settings.
Step 2: In Setting search, type “Content” to go to Content Settings.
Step 3: Open Notifications:
Step 4: Do the same as you did with Google Chrome (explained below):
Eliminate Push Notifications on Safari
Step 1: Open Safari Preferences.
Step 2: Choose the domain from where you like push pop-ups gone and change to "Deny" from "Allow".
What is Karl?
The Karl threat is adware or browser redirect virus. It may slow your computer down siginficantly and display advertisements. The main idea is for your information to likely get stolen or more ads to appear on your device.
The creators of such unwanted apps work with pay-per-click schemes to get your computer to visit risky or different types of websites that may generate them funds. This is why they do not even care what types of websites show up on the ads. This makes their unwanted software indirectly risky for your OS.
What are the symptoms of Karl?
There are several symptoms to look for when this particular threat and also unwanted apps in general are active:
Symptom #1: Your computer may become slow and has poor performance in general.
Symtpom #2: You have toolbars, add-ons or extensions on your web browsers that you don't remember adding.
Symptom #3: You see all types of ads, like ad-supported search results, pop-ups and redirects to randomly appear.
Symptom #4: You see installed apps on your Mac running automatically and you do not remember installing them.
Symptom #5: You see suspicious processes running in your Task Manager.
If you see one or more of those symptoms, then security experts reccomend that you check your computer for viruses.
What types of Unwanted Programs are there?
According to most malware researchers and cyber-security experts, the threats that can currently affect your Mac can be the following types:
- Rogue Antivirus programs.
- Browser hijackers.
- Fake optimizers.
What to do if I have a "virus" like Karl?
Do not panic! You can easily get rid of most adware or unwanted program threats by firstly isolating them and then removing them from your browser and computer. One reccomended way to do that is by using a reputable malware removal software that can take care of the removal automatically for you. There are many anti-malware apps out there that you can choose from. SpyHunter is one of the reccomended anti-malware apps, that can scan your computer for free and detect any viruses, tracking cookies and unwanted adware apps and eliminate them quickly. This saves time when compared to doing the removal manually.
How to secure my passwords and other data from Karl?
With few simple actions. First and foremost, it is imperative that you follow these steps:
Step 1: Find a safe computer and connect it to another network, not the one that your Mac was infected in.
Step 2: Change all of your passwords, starting from your e-mail passwords.
Step 3: Enable two-factor authentication for protection of your important accounts.
Step 4: Call your bank to change your credit card details (secret code, etc.) if you have saved your credit card for online shopping or have done online activiites with your card.
Step 5: Make sure to call your ISP (Internet provider or carrier) and ask them to change your IP address.
Step 6: Change your Wi-Fi password.
Step 7: (Optional): Make sure to scan all of the devices connected to your network for viruses and repeat these steps for them if they are affected.
Step 8: Install anti-malware software with real-time protection on every device you have.
Step 9: Try not to download software from sites you know nothing about and stay away from low-reputation websites in general.
If you follow these reccomendations, your network and all devices will become significantly more secure against any threats or information invasive software and be virus free and protected in the future too.
More tips you can find on our website, where you can also ask any questions and comment underneath the articles about your computer problems. We will try to respond as fast as possible.