The Rapid virus falls within the MedusaLocker ransomware family. Harmful software of such sort encrypts all the data on your computer (photos, documents, excel tables, music, videos, etc) and adds its specific extension to every file, leaving the How_to_back_files.html text files in every folder which contains the encrypted files.
What is Rapid virus?
☝️ Rapid is a MedusaLocker family ransomware-type virus.
Rapid will add its extra .rapid4 extension to the title of each encoded file. The number in the end is unique for each attack instance. In our case, a file entitled “photo.jpg” was changed to “photo.jpg.rapid4”. Just like the Excel table with the name “table.xlsx” became “table.xlsx.rapid4”, and so on.
In each folder that contains the encoded files, a How_to_back_files.html text document will be created. It is a ransom money note. Therein you can find information about the ways of contacting the racketeers and some other information. The ransom note most probably contains instructions on how to buy the decryption tool from the tamperers. You can get this decryptor after contacting [email protected] via email. That is it.
Rapid Overview:
| Name | Rapid Virus |
| Ransomware family1 | MedusaLocker ransomware |
| Extension | .rapid4 |
| Ransomware note | How_to_back_files.html |
| Contact | [email protected] |
| Detection | Trojan:Win32/StealC.MZX!MTB, Trojan:MSIL/LokiBot.SET!MTB, UDS:Trojan-Ransom.Win32.PornoAsset |
| Symptoms | Your files (photos, videos, documents) get a .rapid4 extension and you can’t open them. |
| Fix Tool | See If Your System Has Been Affected by Rapid virus |
The How_to_back_files.html document coming in package with the Rapid malware states the following:
YOUR PERSONAL ID: - /!\\ YOUR COMPANY NETWORK HAS BEEN PENETRATED /!\\ All your important files have been encrypted! Your files are safe! Only modified. (RSA+AES) ANY ATTEMPT TO RESTORE YOUR FILES WITH THIRD-PARTY SOFTWARE WILL PERMANENTLY CORRUPT IT. DO NOT MODIFY ENCRYPTED FILES. DO NOT RENAME ENCRYPTED FILES. No software available on internet can help you. We are the only ones able to solve your problem. We gathered highly confidential/personal data. These data are currently stored on a private server. This server will be immediately destroyed after your payment. If you decide to not pay, we will release your data to public or re-seller. So you can expect your data to be publicly available in the near future.. We only seek money and our goal is not to damage your reputation or prevent your business from running. You will can send us 2-3 non-important files and we will decrypt it for free to prove we are able to give your files back. Contact us for price and get decryption software. email: [email protected] [email protected] * To contact us, create a new free email account on the site: protonmail.com IF YOU DON\'T CONTACT US WITHIN 72 HOURS, PRICE WILL BE HIGHER. * Tor-chat to always be in touch:
In the screenshot below, you can see what a folder with files encrypted by the Rapid looks like. Each filename has the “.rapid4” extension added to it.
How did my computer get infected with Rapid ransomware?
There are many possible ways of ransomware injection.
There are currently three most exploited methods for evil-doers to have the Rapid virus working in your system. These are email spam, Trojan infiltration and peer-to-peer networks.
- If you open your inbox and see emails that look like familiar notifications from utility services companies, delivery agencies like FedEx, Internet providers, and whatnot, but whose sender is unknown to you, be wary of opening those emails. They are most likely to have a ransomware file attached to them. Thus it is even more dangerous to download any attachments that come with letters like these.
- Another option for ransom hunters is a Trojan horse model. A Trojan is a program that gets into your PC pretending to be something legal. For instance, you download an installer for some program you need or an update for some program. But what is unpacked turns out to be a harmful program that corrupts your data. As the installation package can have any name and any icon, you have to make sure that you can trust the source of the stuff you’re downloading. The optimal way is to use the software developers’ official websites.
- As for the peer file transfer protocols like torrent trackers or eMule, the danger is that they are even more trust-based than the rest of the Web. You can never guess what you download until you get it. Our suggestion is that you use trustworthy websites. Also, it is a good idea to scan the directory containing the downloaded objects with the antivirus as soon as the downloading is finished.
How to remove ransomware?
It is important to inform you that besides encrypting your data, the Rapid virus will probably install Vidar Stealer on your PC to get access to credentials to various accounts (including cryptocurrency wallets). The mentioned spyware can extract your logins and passwords from your browser’s auto-filling cardfile.
How to avert ransomware injection?
Rapid ransomware has no superpower, neither does any similar malware.
You can defend your PC from ransomware infiltration in several easy steps:
- Ignore any emails from unknown senders with strange addresses, or with content that has nothing to do with something you are expecting (can you win in a lottery without even taking part in it?). In case the email subject is likely something you are expecting, scrutinize all elements of the questionable email with caution. A fake email will surely contain a mistake.
- Avoid using cracked or untrusted software. Trojans are often shared as an element of cracked software, most likely as a “patch” preventing the license check. Understandably, untrusted programs are very hard to tell from trustworthy software, because trojans may also have the functionality you need. Try searching for information on this program on the anti-malware message boards, but the best way is not to use such programs at all.
Frequently Asked Questions
🤔 How can I open “.rapid4” files?Are the “.rapid4” files accessible?
Negative. That is why ransomware is so frustrating. Until you decode the “.rapid4” files you will not be able to access them.
🤔 The encrypted files are very important to me. How can I decrypt them quickly?
If the “.rapid4” files contain some really important information, then you probably have them backed up. In case you haven’t, there is still a chance that you do have a Restore Point from some time ago to roll back the whole system to the moment when it had no virus yet, but already had your files. There are other ways to beat ransomware, but they take time.
🤔 What actions should I take if the Rapid malware has blocked my PC and I can’t get the activation code.
🤔 What can I do right now?
Many of the encrypted files might still be at your disposal
- If you exchanged your important files via email, you could still download them from your online mailbox.
- You may have shared photographs or videos with your friends or relatives. Simply ask them to post those pictures back to you.
- If you have initially downloaded any of your files from the Internet, you can try doing it again.
- Your messengers, social networks pages, and cloud storage might have all those files as well.
- It might be that you still have the needed files on your old PC, a laptop, mobile, external storage, etc.
HINT: You can employ file recovery utilities2 to get your lost data back since ransomware encodes the copies of your files, removing the authentic ones. In the video below, you can see how to recover your files with PhotoRec, but remember: you can do it only after you kill the ransomware itself with an anti-malware program.

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