Here you will find out more about the issues caused by a ransomware infection dubbed .cat virus files. At the end of the article, there is a detailed guide on how to remove the infection and secure the PC. If you want to try to recover locked .cat files with the help of alternative methods you will find some of them in one of the steps in the guide.
.cat Virus Files
The infection called .cat virus files is actually a data locker ransomware. Is was reported as a strain of the Xorist threat family which means that it will contaminate essential system settings, disrupt PC security and encode personal files to extort a ransom. Since the encryption module of the Cat virus is set to use a sophisticated cipher algorithm, all files that appear with the extension .cat in their names remain completely inaccessible.
Cat Virus Summary
| Name | Cat also known as Win32:Filecoder-M [Trj] (Avast), Trojan.Ransom.AIG (BitDefender), Trojan-Ransom.Win32.Xorist.lk (Kaspersky) |
| Type | Ransomware, Cryptovirus |
| Ransom Note | КАК РАСШИФРОВАТЬ ФАЙЛЫ.txt |
| Short Description | The threat encrypts target files stored on your computer, marks them with the .cat extension and extorts a ransom by displaying a ransom message. |
| Symptoms | Important files are encoded and renamed with .cat extension. You cannot open them. Hackers demand a ransom payment. |
| Distribution Method | Spam Emails, Email Attachments |
| Detection Tool |
See If Your System Has Been Affected by malware
Download
Malware Removal Tool
|
.cat Virus In Details
There is a new Xorist ransomware strain and it is the Cat virus. Currently, samples of this ransomware have been circling the web to find their victims. The most probable spread technique is malspam.
Malspam enables hackers to deliver malicious code on users’ devices with the help of specially crafted email messages. Such email messages usually have one or more of the following traits:
- A link to a compromised web page that hosts the ransomware payload on it.
- Or a malicious file attachment that is presented as legitimate document.
The moment you open an infected web page in your browser, it may download and execute ransomware infection files directly on the PC. As regards file attachments, they could appear as .rar or .zip archives that contain the malicious code that will trigger an infection with Cat ransomware.
When the infection process with the so-called .cat virus files begins, the virus drops additional malicious files on the system. It is likely that the virus will drop these files in some of the following folders:
- %AppData%
- %Local%
- %LocalLow%
- %Roaming%
- %Temp%
As a result of infection with the Cat ransomware virus, your PC will be more vulnerable to additional malware attacks until all ransomware files are uninstalled and deleted.
Ransomware programs like Cat contaminate the settings of various essential system components to complete the attack to the end. Affected by the threat are likely to be some crucial registry keys stored by the Registry Editor.
To be more precise the keys Run and RunOnce may be infected by .cat virus. Here are the exact registry locations that should be checked for malicious entries during the removal process:
→ HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
The reason for the contamination of these keys is their ability to execute various files and apps automatically. So once Cat ransomware has its malicious entries added under the Run key, it becomes able to load automatically every time you start the infected operating system.
When it’s turn to the data encryption stage, Cat ransomware utilizes strong cipher algorithms to encrypt personal files. Similar to its predecessors – Mame vse and Ssghl, Cat virus is likely to scan infected systems for all files that have one of following extensions. Whenever a match is available it encodes the file by transforming parts of its original code:
→.zip, .rar, .7z, .tar, .gzip, .jpg, .jpeg, .psd, .cdr, .dwg, .max, .bmp, .gif, .png, .doc, .docx, .xls, .xlsx, .ppt, .pptx, .txt, .pdf, .djvu, .htm, .html, .mdb, .cer, .p12, .pfx, .kwm, .pwm, .1cd, .md, .mdf, .dbf, .odt, .vob, .ifo, .lnk, .torrent, .mov, .m2v, .3gp, .mpeg, .mpg, .flv, .avi, .mp4, .wmv, .divx, .mkv, .mp3, .wav, .flac, .ape, .wma, .ac3
The appearance of the extension .cat in the name of a file is a sure sign that you won’t be able to open this file. And that’s why you will be presented with a ransom message dropped by the ransomware. The message is stored by a file named КАК РАСШИФРОВАТЬ ФАЙЛЫ.txt. What you could read when you open this file is the following:
Внимание! Все Ваши файлы зашифрованы!
Чтобы восстановить свои файлы и получить к ним доступ,
отправьте смс с текстом XXXX на номер YYYYУ вас есть N попыток ввода кода. При превышении этого
количества, все данные необратимо испортятся. Будьте
внимательны при вводе кода!
Apparently, the purpose of this file is to blackmail you into contacting hackers in order to receive further instructions on ransom payment by them. What we could advise you is to avoid what this message states and attempt to cope with ransomware impacts with the help of secure methods that won’t expose your system, privacy, and money at the risk of further abuses.
Remove Cat Virus and Try to Restore Data
The Xorist ransomware strain associated with .cat extension is a threat with highly complex code that plagues not only your files but your whole system. So you should properly clean and secure your infected system before you could use it regularly again. Below you could find a step-by-step removal guide that may be helpful in attempting to remove this ransomware. Choose the manual removal approach if you have previous experience with malware files. If you don’t feel comfortable with the manual steps select the automatic section from the guide. Steps there enable you to check the infected system for ransomware files and remove them with a few mouse clicks.
If you want to understand how to potentially fix encrypted files with the help of alternative data recovery approaches, make sure to read carefully all details mentioned in the step “Restore files”. We remind you that before you begin with the data recovery process, you should back up all encrypted files to an external drive as this will help you to prevent their irreversible loss.
Gergana Ivanova
Highly motivated writer with 5+ years of experience writing for ransomware, malware, adware, PUPs, and other cybersecurity-related issues. As a writer, I strive to create content that is based on thorough technical research. I find joy in the process of creating articles that are easy to understand, informative, and useful. Follow me on Twitter (@IRGergana) for the latest in the field of computer, mobile, and online security.
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Attention! SensorsTechForum strongly recommends that all malware victims should look for assistance only by reputable sources. Many guides out there claim to offer free recovery and decryption for files encrypted by ransomware viruses. Be advised that some of them may only be after your money.
As a site that has been dedicated to providing free removal instructions for ransomware and malware since 2014, SensorsTechForum’s recommendation is to only pay attention to trustworthy sources.
How to recognize trustworthy sources:
- Always check "About Us" web page.
- Profile of the content creator.
- Make sure that real people are behind the site and not fake names and profiles.
- Verify Facebook, LinkedIn and Twitter personal profiles.
About the Cat Virus Research
The content we publish on SensorsTechForum.com, this Cat Virus how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific malware and restore your encrypted files.
How did we conduct the research on this ransomware?
Our research is based on an independent investigation. We are in contact with independent security researchers, and as such, we receive daily updates on the latest malware and ransomware definitions.
Furthermore, the research behind the Cat Virus ransomware threat is backed with VirusTotal and the NoMoreRansom project.
To better understand the ransomware threat, please refer to the following articles which provide knowledgeable details.
References
1. How to Recognize Spam Emails with Ransomware
2. How Does Ransomware Encryption Work?
3. How to Decrypt Ransomware Files
4. Ransomware Getting Greedier and Bigger, Attacks Increase by 40%
5. 1 in 5 Americans Victim of Ransomware
How to Remove Cat Virus from Windows.
Step 1: Boot Your PC In Safe Mode to isolate and remove Cat Virus
1. Hold Windows Key + R.
2. The "Run" Window will appear. In it, type "msconfig" and click OK.
3. Go to the "Boot" tab. There select "Safe Boot" and then click "Apply" and "OK".
4. When prompted, click on "Restart" to go into Safe Mode.
5. You can recognise Safe Mode by the words written on the corners of your screen.
Step 2: Uninstall Cat Virus 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. To do that:
1. Hold the Windows Logo Button and "R" on your keyboard. A Pop-up window will appear.
2. In the field type in "appwiz.cpl" and press ENTER.
3. This will open a window with all the programs installed on the PC. Select the program that you want to remove, and press "Uninstall"
Follow the instructions above and you will successfully uninstall most programs.
Step 3: Clean any registries, created by Cat Virus on your computer.
The usually targeted registries of Windows machines are the following:
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
- HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
You can access them by opening the Windows registry editor and deleting any values, created by Cat Virus 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.
Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.
Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.
Step 4: Scan for Cat Virus 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 Guide for Automatic and Fast Removal
Step 5 (Optional): Try to Restore Files Encrypted by Cat Virus.
Ransomware infections and Cat Virus aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.
1. Download the recommended Data Recovery software by clicking on the link underneath:
Simply click on the link and on the website menus on the top, choose Data Recovery - Data Recovery Wizard for Windows or Mac (depending on your OS), and then download and run the tool.
Step 6: How to Restore Files Encrypted by Ransomware (Video Guide)
Get rid of Cat Virus from Mac OS X.
Step 1: Uninstall Cat Virus 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 Cat Virus:
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 Cat Virus. 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 Cat Virus. 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 Cat Virus 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 Cat Virus. If you believe there is no such file, do not delete anything.
You can repeat the same procedure with the following other Library directories:
→ ~/Library/LaunchAgents
/Library/LaunchDaemons
Tip: ~ is there on purpose, because it leads to more LaunchAgents.
Step 3 (Optional): Try to Restore Files Encrypted by Cat Virus.
Ransomware infections and Cat Virus aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.
1. Download the recommended Data Recovery software by clicking on the link underneath:
Simply click on the link and on the website menus on top, choose Data Recovery - Data Recovery Wizard for Windows or Mac (depending on your OS), and then download and run the tool.
Cat Virus FAQ
What is Cat Virus ransomware and how does it work?
Cat Virus is a ransomware infection - the malicious software that enters your computer silently and blocks either access to the computer itself or encrypt your files.
Many ransomware viruses use sophisticated encryption algorithm how to make your files inaccessible. The goal of ransomware infections is to demand that you pay a ransom payment to get access to your files back.
How does Cat Virus ransomware infect my computer?
Via several ways.Cat Virus Ransomware infects computers by being sent via phishing e-mails, containing virus attachment.
This attachment is usually masked as an important document, like an invoice, bank document or even a plane ticket and it looks very convincing to users.
After you download and execute this attachment, a drive-by download occurs and your computer is infected with the ransomware virus.
Another way, you may become a victim of Cat Virus is if you download a fake installer, crack or patch from a low reputation website or if you click on a virus link. Many users report getting a ransomware infection by downloading torrents.
How to open .Cat Virus files?
You can't. At this point the .Cat Virus files are encrypted. You can only open them once they are decrypted.
Decryptor did not decrypt my data. What now?
Do not panic and backup the files. If a decryptor did not decrypt your .Cat Virus files successfully, then do not despair, because this virus is still new.
One way to restore files, encrypted by Cat Virus ransomware is to use a decryptor for it. But since it's a new virus, advised that the decryption keys for it may not be out yet and available to the public. We will update this article and keep you posted as soon as this decryptor is released.
How Do I restore ".Cat Virus" files (Other Methods)?
Yes, sometimes files can be restored. We have suggested several file recovery methods that could work if you want to restore .Cat Virus files.
These methods are in no way 100% guarantee that you will be able to get your files back. But if you have a backup, your chances of success are much greater.
How do I get rid of Cat Virus ransomware virus?
The safest way and the most efficient one for the removal of this ransomware infection is the use a professional anti malware software. It will scan for and locate Cat Virus ransomware and then remove it without causing any additional harm to your important .Cat Virus files.
Also, keep in mind that viruses like Cat Virus ransomware also install Trojans and keyloggers that can steal your passwords and accounts. Scanning your computer with an anti-malware software will make sure that all of these virus components are removed and your computer is protected in the future.
What to Do If nothing works?
There is still a lot you can do. If none of the above methods seem to work for you, then try these methods:
- Try to find a safe computer from where you can can login on your own line accounts like One Drive, iDrive, Google Drive and so on.
- Try to contact your friends, relatives and other people so that they can check if they have some of your important photos or documents just in case you sent them.
- Also, check if some of the files that were encrypted it can be re-downloaded from the web.
- Another clever way to get back some of your files is to find another old computer, a flash drive or even a CD or a DVD where you may have saved your older documents. You might be surprised what will turn up.
- You can also go to your email account to check if you can send any attachments to other people. Usually what is sent the email is saved on your account and you can re-download it. But most importantly, make sure that this is done from a safe computer and make sure to remove the virus first.
More tips you can find on our forums, where you can also asks any questions about your ransomware problem.
How to Report Ransomware to Authorities?
In case your computer got infected with a ransomware infection, you can report it to the local Police departments. It can help authorities worldwide track and determine the perpetrators behind the virus that has infected your computer. Below, we have prepared a list with government websites, where you can file a report in case you are a victim of a cybercrime:
Cyber-security authorities, responsible for handling ransomware attack reports in different regions all over the world:
- Germany - Offizielles Portal der deutschen Polizei
- United States - IC3 Internet Crime Complaint Centre
- United Kingdom - Action Fraud Police
- France - Ministère de l'Intérieur
- Italy - Polizia Di Stato
- Spain - Policía Nacional
- Netherlands - Politie
- Poland - Policja
- Portugal - Polícia Judiciária
- Greece - Cyber Crime Unit (Hellenic Police)
- India - Mumbai Police - CyberCrime Investigation Cell
- Australia - Australian High Tech Crime Center
Reports may be responded to in different timeframes, depending on your local authorities.
