Clop ransomware (Virus Removal Instructions) - updated Mar 2019

What is Clop ransomware?

Clop ransomware is evasive malware that targets corporate networks instead of regular computer users

Clop ransomware is a file locking virus that enters without users noticing encrypts all personal file with AES encryption algorithm

Clop ransomware is a data locker that belongs to CryptoMix virus family and uses various obfuscation techniques to actively avoid detection. For example, the main executable often comes digitally signed with a valid certificate, which allows the virus to bypass detection.^[1] It uses AES cipher to encrypt pictures, videos, music, databases documents, and appends .CLOP or .CIOP file extension, which prevents victims from accessing personal data. Hackers behind the threat ask users in ransom note ClopReadMe.txt to contact them via specified email addresses (for example, icarsole@protonmail.com) and pay in Bitcoin for the alleged file decryptor. Clop ransomware authors threaten victims to delete the decryption tool if they fail to reach out cybercriminals within two weeks. As usual, users are not recommended contacting virus developers and instead use alternative file recovery methods. The newest variant of Clop virus shuts down anti-virus software, startup repair feature, and multiple Windows processes in order to perform file encryption without interruption. Additionally, the ransom note is directed towards companies instead of regular users, which means that malware authors are focusing on Big game hunting – a trend that is becoming more prevalent among ransomware developers due to increased profit margins.

Interestingly, the Clop virus' name comes from a Russian “klop,” which means “bed bug” – a bug that sucks blood from its victims when they are asleep.

Clop ransomware can be injected with a variety of methods, such as:

• Spam email attachments or hyperlinks;
• Unprotected RDP connection;
• Compromised or hacker-created websites
• Re-packed installers;
• Keygens, cracks, and other executables;
• Exploit kits, etc.

Clop ransomware is crypto malware that comes from CryptoMix virus family

Once inside the system, Clop virus grants itself elevated privileges with the help of a fake certificate issued to the executable and launches the clearnetworkdns_11-22-33.bat file. This allows malware to overwrite and modify system files. It also reads several technical details like computer name or CPU data and sends it off to hackers. Additionally, Clop ransomware creates \Users\CIiHmnxMn6Ps folder where more malicious files are executed.

Clop ransomware then scans the device for files to encrypt. It targets most commonly used files, such as .jpg, .mp3, .doc, .mkv, and many others. After encryption, a file like picture.jpg is turned into picture.jpg.Clop, and becomes inaccessible.

Note that data is not corrupted; it is merely locked by a key that only hackers have access to. However, encryption can sometimes be bypassed when using third-party software. Nevertheless, you need to remove Clop ransomware before attempting file recovery, or otherwise, they will get encrypted repeatedly.

One of the ClopReadMe.txt ransom notes states:

*_*Your network has been penetrated*_*
All files on each host in the network have been encrypted with a strong algorithm!
Backups were either encrypted or deleted or backup disks were formatted!
Shadow copies also removed, so F8 or any other methods may damage encrypted data but not recover!
We exclusively have decryption software for your situation!
===No DECRYPTION software is AVAILABLE in the PUBLIC===
– DO NOT DELETE readme files.
– DO NOT RENAME OR MOVE the encrypted or readme files.
– DO NOT RESET OR SHUTDOWN – files may be damaged.
—THIS MAY LEAD TO THE IMPOSSIBILITY OF RECOVERY OF THE CERTAIN FILES—
—A:: REPAIR TOOLS ARE USELESS AND CAN DESTROY YOUR FILES IRREVERSIBLY—
<…>

Despite warnings from malware authors, you should proceed with Clop ransomware removal. Do not try to accomplish that yourself – the virus modified multiple system files and finding and deleting them manually is almost impossible. Thus, use anti-malware software that can recognize the threat. We recommend installing FortectIntego or SpyHunter 5Combo Cleaner.

Clop virus authors actively try to discourage users from using alternative file recovery methods. Be aware that it is in their best interest to make victims believe that no other recovery method is possible

Ransomware avoidance technique is simple – be attentive online

Malicious actors usually are intelligent people, that is why they are continually developing their scripts, obfuscating them better and employing sophisticated techniques to spread the virus. However, most of the users who adopt basic security measures can avoid most of the cyber infections, industry experts^[3] point out.

The primary security measures against ransomware include the installation of security software. There are plenty on the market to choose from, but be sure not to download rogue anti-spyware – tools that flag thousands of fraudulent issues and then demand payment for its full version. These tools will not only fail to protect you but might also infect your device with adware or other PUPs. Thus, make sure you pick reputable AV engines.

Other things you should do include:

• Prepare backups of your files as required;
• Avoid visiting high-risk sites;
• Update your system and programs as soon as security patches come out;
• Do not casually open spam email attachments or click on links;
• Use ad-blocker;
• Do not download cracks, keygens, and similar hacking tools;
• Enable Firewall;
• Do not click on the content on sites you get randomly redirected to;
• Disable Adobe Flash or only download its updates from the official website.^[4]

Terminate Clop ransomware with the help of anti-malware software

To remove Clop virus, you will have to employ anti-malware software that can detect the payload. Be aware that the threat might use some obfuscation techniques (it is known that the threat delays some of its processes by up to five minutes).^[5] In such a case, enter Safe Mode with Networking as explained below and perform full system scan using FortectIntego, SpyHunter 5Combo Cleaner, or another trusted security application.

Once you are done with Clop ransomware removal, you can attempt to recover your data. Unfortunately, there is no known method that would work 100%, apart from if you retrieve your files from backups. If you did not have any prepared, you should rely on third-party software that does not decipher records, but instead extracts the working versions from the computer. Additionally, some malware, while programmed to delete Windows backups, fails to remove Shadow Volume copies, giving an excellent opportunity to reclaim all the data.