How to remove CILLA ransomware

CILLA ransomware is a file locking threat that tries to imitate Maoloa virus

CILLA ransomware is a type of malware that focuses on money extortion and comes from a well-known malware family – GlobeImposter 2.0. Soon after infiltration, the virus encrypts all pictures, videos, documents, and other data by using a strong encryption algorithm AES-256^[1] and appends .CILLA extension to each of the files. To retrieve the access to data, users are asked to email hackers via blackcilla@qq.com or blackcilla@cock.li and pay a ransom in Bitcoin, the amount of which is not stated in the ransom note how_to_back_files.html.

Unlike most file locking viruses, CILLA ransomware tries to imitate another crypto-locking malware Maola – it is done deliberately to prevent security experts from identifying the infection correctly. Nevertheless, this does not make any difference to the affected users, as a result in both cases is the same – locked data. Unfortunately, there is no CILLA ransomware decryptor currently available, although there are other methods that might be able to help you recover your files.

Just as any other large ransomware family member, CILLA ransomware is spread with the help of various methods, including:

• Spam emails
• Exploit kits^[2]
• Software cracks
• Pirated software installers
• Unprotected RDP connections
• Fake updates, etc.

In some cases, malicious actors are also known to insert a legitimate program Process hacker or Process Hacker 2 into the infected system in order to monitor it and perform other malicious activities. Nevertheless, this unwanted activity can be detected and stopped by most of the up-to-date security tools, which can also help with CILLA removal.

Once CILLA ransomware gets into the machine, it starts the preparation for the file encryption process. For example, it deletes several files (such as Windows' automatic file backups) and modifies the Windows registry to run without interruptions. After that, the virus targets the most common file types like .doc, .html, .jpg, .mp4, .ppt, and others, all while skipping executables, as well as system files.

The dropped ransom note how_to_back_files.html states the following:

☠ YOUR FILES ARE ENCRYPTED! ☠
ALL YOUR IMPORTANT DATA HAS BEEN ENCRYPTED.

To recover data you need decryptor.
To get the decryptor you should:
Send 1 test image or text file blackcilla@qq.com or blackcilla@cock.li.
In the letter include your personal ID (look at the beginning of this document).

We will give you the decrypted file and assign the price for decryption all files
After we send you instruction how to pay for decrypt and after payment you will receive a decryptor and instructions We can decrypt one file in quality the evidence that we have the decoder.
Attention!

Only blackcilla@qq.com and blackcilla@cock.li can decrypt your files
Do not trust anyone blackcilla@qq.com and blackcilla@cock.li
Do not attempt to remove the program or run the anti-virus tools
Attempts to self-decrypting files will result in the loss of your data
Decoders other users are not compatible with your data, because each user's unique encryption key

As evident, the crooks are trying to intimidate victims and make them pay the ransom. However, security experts^[3] do not recommend contacting cybercriminals, as there is no guarantee that they will send required decryption software after the payment in Bitcoin. Additionally, paying crooks behind the CILLA virus will only fuel their will to produce more advanced viruses and infect more users.

While it is true that, in some cases, the files might get damaged after you remove CILLA ransomware, there is a solution for that. Before you do anything, you should backup all the encrypted data and then access Safe Mode to get rid of the virus with the help of reputable security software that can recognize the threat. According to Virus Total,^[4] most security tools should be able to detect and eliminate the infection. CILLA ransomware is identified as follows:

• HEUR/AGEN.1011584
• Win32:Trojan-gen
• Ransom:Win32/Filecoder.RB!MSR
• Ransom_FAKEGLOBE.SMB
• Generic.Ransom.GlobeImposter.4361C1A9
• Heuristic.HEUR/AGEN.1011584, etc.

After that, you can try using third-party recovery tools to retrieve .CILLA encrypted files. If you are having Windows system issues after the infection, instead of reinstalling the OS, you could also run a scan with FortectIntego.

There are several ways to protect yourself from ransomware intrusion

Some cybercriminals are implementing various methods when it comes to the illegal ransomware business. One thing is clear: ransomware is on the rise, and there are multiple hacking groups with highly established networks – these gangs infect thousands of users worldwide, as well as various businesses and organizations, resulting in millions of dollars in repair costs. While it is impossible to avoid ransomware completely, however, there are several ways to diminish that chance to a minimum.

The first step for a more secure computer is automated protection – anti-malware software. There are plenty of security tools available, and most of them even employ a separate feature that enables ransomware protection (so make sure it is always on). However, defenses provided by anti-malware software are never enough, and you should also be very careful when spending time online, opening emails, and downloading files. Here's what to do to increase your PC security level:

• Do not open spam email attachments (files that ask you enable macros are most likely viruses) or click on hyperlinks inside;
• Patch your Windows OS along with all the installed software immediately when the updates are available;
• Avoid visiting high-risk websites like torrents, porn, gambling, etc. (if you do, enable ad-block for extra protection);
• Do not download and use software cracks or pirated program installers;
• Use strong passwords for all your accounts and never reuse them. Also, enable two-factor authentication where possible;
• Backup all your files as required;

To conclude, a combination of careful web browsing habits and comprehensive security solutions should be enough to keep even the most dangerous malware away.

Do not listen to cybercriminals and remove CILLA ransomware immediately

As already mentioned, it is true that CILLA ransomware removal might compromise the encrypted data permanently. To prevent that, you should immediately copy all the files to an external drive (flash USB or external HDD) or virtual drive (Google Drive, OneDrive, Dropbox, etc.). Once that is done, you need to ensure that you remove CILLA ransomware correctly.

It is not uncommon for crypto-malware to disable anti-virus software like Microsoft Defender. In such a way, hackers might prevent users from getting rid of the malicious payload and attempting alternative data recovery methods. In such a case, you should access Safe Mode with Networking and scan the machine with anti-malware software like SpyHunterCombo Cleaner or MalwarebytesMalwarebytes and get rid of CILLA virus infection.

For .CILLA file recovery, you can either refer to the section below for various methods (keep in mind that chances of retrieving locked files with recovery software are relatively low) and risk your money and pay criminals for a decryption key, which is not recommended.