Cosd ransomware might cause you to lose access to your files permanently
Cosd ransomware is a computer infection that encrypts data on a victim's computer and demands to purchase a decryption tool required to regain access to said files. It also renames encrypted data by appending .cosd extension to all original filenames. All files are encoded with a military-grade RSA 2048 coding algorithm and might be indecipherable without the intervention of the cybercriminals. Although contacting them or paying the ransom is highly recommended.
Following successful encryption, ransomware generates a ransom note, titled _readme.txt, and places it on the desktop so the victims would find it easily. The note contains instructions and persuasion techniques to convince victims to contact their assailants via helpmanager@mail.ch, restoremanager@airmail.cc, helpmanager@airmail.cc emails, and purchase their decryption tool. Its price varies depending on how quickly victims establish contact – if that's done within 72 hours, the price is $490. If they're not hasty, the price will be doubled to $980.
This virus derives from the infamous Djvu ransomware family that's been threatening regular computer users around the world since December 2018. This is the 279th version of the particular threat. Each week new variations, such as the Pola virus, Wbxd virus, Coos virus, are created and spread on the internet. Therefore, companies like Emisoft have dedicated their time to fight these cybercriminals by creating free decryptors for their victims. Although not all strains are decryptable, you can still download their tool and give it a go.
You have alternate options like data recovery tools or functions of the OS, but the best way to repair those files – data backups from different devices. This is possible after the virus termination. This article contains a summary of the culprit, its delivery techniques, and of course – removal guide. Down below, you can find all the options that are possibly useful for the encoded file recovery.
| name | Cosd ransomware |
|---|---|
| Type | Cryptovirus, file-locker |
| Family | Djvu/STOP ransomware |
| Appended file extension | Non-system files (pics, documents, archives, etc.) are appended with .cosd extension |
| Ransom note | _readme.txt can be found on the desktop of the infected machine |
| Ransom amount | $490/$980 |
| Criminal contact details | Two emails are provided to establish contact with the assailants: helpmanager@mail.ch, helpmanager@airmail.cc |
| Distribution | Spam emails, file-sharing platforms, especially torrent sites |
| Malware removal | Trustworthy anti-malware tools should be used to eliminate any kind of malware fully |
| System repair | Various system files and settings get corrupted and damaged during the encryption. Victims should use the powerful FortectIntego system repair tool to fix any system irregularities |
Ransomware leave ransom notes after encrypting personal data, such as documents, archives, databases, etc. It creates a text file named _readme.txt and leaves it on the desktop. Within it, cybercriminals reassure their victims that their files can be retrieved if they pay the requested amount of money. Although the preferred payment method isn't specified, we can speculate that criminals will ask for cryptocurrency Bitcoins.
To convince users to meet their demands, cybercriminals use many techniques. They offer free decryption of a single file from the infected machine and provide a link to a video where the said decryptor can be seen in action. Moreover, they offer a 50% discount for the ones who contact them within 72 hours. To put it in other words, hackers try to push victims into making rash decisions.
The whole message in the _readme.txt file reads:
ATTENTION!
Don't worry, you can return all your files!
All your files like pictures, 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:
https://we.tl/t-EtT4dX8q3X
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:
helpmanager@mail.chReserve e-mail address to contact us:
helpmanager@airmail.ccYour personal ID:
Needless to say that we stand on the same side with the FBI,[1] other authorities, and cybersecurity specialists when it comes to contacting the criminals and paying them. Ransomware victims should never do that, as that's the only way to stop this malicious software from spreading. Criminals go where the money goes. If there's no money in ransomware, they will seize to develop it.
Therefore, our cybersecurity team has assembled the best options to remove Cosd ransomware. First of all, if you had an anti-malware solution installed on your device before it was infected, it could mean two things – either its virus database was out of date, or it's incapable of stopping serious malware.
Our team suggests using trustworthy anti-malware tools like SpyHunterCombo Cleaner or MalwarebytesMalwarebytes that will not only successfully accomplish malware removal but protect your devices from such hazards in the future. Run a full threat scan and eliminate any and all suspicious files that it suggests to do so.
Now that the virus is taken care of, it's time for the computer system itself. Ransomware, and especially the ones from Djvu lineage, do extensive damage to key system files. Thus they need attention, or your device will function improperly. If you down have powerful system repair tools, experts[2] recommend using the FortectIntego tune-up tool or similar software. When these steps are completed, you're safe to restore your data from backups and enjoy your device anew.
File-sharing platforms: the most popular Djvu ransomware delivery technique
Ransomware attacks have been around for decades[3] and if people don't stop paying their assailants – they won't go anywhere anytime soon. There are many file-locking virus versions created, and they can be spread using different distribution techniques, including RDP attacks, spam emails, deceptive ads, and so on.
Our cybersecurity team has finished research showing that most Djvu family ransomware is hidden in (thus delivered through) file-sharing platforms, especially most-visited torrent portals. Cybercriminals realized that they could exploit the weakness of people who want to cheat the system by getting licensed, commercial software for free.
Hackers used catchy names to camouflage their creations and attract gullible people. Few examples of how ransomware was disguised as:
- cracks for the latest, most popular games,
- unlocked expensive applications,
- cracks for commercial software,
- game cheat codes.
So if you value your files, security, money, and privacy, we advise you to refrain from using torrent sites altogether. Ransomware could be hidden in practically any torrent. Support your beloved, desired software developers by purchasing their products from them or official distributors.
Use security software to delete ransomware from your machine
Suppose you've spotted any indications such as _readme.txt ransom note, or .cosd extension appended to your files, then your anti-malware software failed you, and your device is infected with Djvu ransomware. The good news is that that's not the end of the world as this cryptovirus can be removed, and there's even a possibility to restore your files (if you didn't keep backups).
First of all, you should try the decryption software offered by Emisoft, as they specialize in helping people after Djvu family ransomware attacks. Keep in mind that not all cryptoviruses from this lineage are decyphered, so the decryptor might not be right for you. If it doesn't work, then export all encrypted files to an offline storage device and check back with us later as we update our readers with the latest news.
When that's done, you will need anti-malware software to proceed with removal. If you don't own one, we recommend getting professional tools such as SpyHunterCombo Cleaner or MalwarebytesMalwarebytes. Launch it and scan the entire computer system. Remove any suspicious files. If the file-locker virus disabled anti-malware software, then reboot your device and start it in Safe Mode with Networking and launch the security tool then. If you're unsure how to access this mode, please scroll down as we display the full instructions below.
Cosd ransomware virus, like most of its family members, makes various changes to system files and settings. That could impede normal system behavior by disabling anti-malware tools, preventing from visiting security-related websites, and many other issues. To restore all these changes and get your system back on its feet, we advise using the FortectIntego system repair tool.
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