How to remove Zepto virus

Zepto ransomware is an alternative version of the infamous Locky file-encrypting virus

Zepto ransomware is one of the dangerous Locky virus versions which performs data encryption. This ransomware family is considered to be one of the most hazardous cyber threats of 2016 and spreads via malicious spam emails^[1] – he malspam campaign is detected spreading via Necurs botnet. Precisely, malicious JavaScript files are packed inside of .zip or .docm (macro-embedded MS Word documents) files which, once opened, begin the infection routine of a Windows machine. According to the researchers, approximately 150 thousand emails were holding the obfuscated payload of Zepto virus as an attachment^[2].

There are several major difference between Locky and Zepto ransomware, however. Malware uses the combination of AES 128 and RSA 2048 algorithms to encode information, and not only appends .zepto extension, but also modifies the rest of the file name components. Each file is changed in the following way: [8 digit hexadecimal string]-[4 digit hexadecimal string]-[4 digit hexadecimal string]-[12 digit hexadecimal string].zepto. Malware then delivers _HELP_instructions.html ransom note which asks to pay ransom in bitcoin. Additionally, desktop wallpaper is also swapped by a _HELP_instructions.bmp image.

Researchers do not recommend contacting ransomware virus authors, as there is a working decryption tool that should be able to remove .zepto extension for free, and allow to use data once again. But before that, make sure you clean your computer from the infection and malicious files – find out how below.

The latest versions detected of Zepto ransomware are Lukitus and Ykcol. Users are tricked into downloading an infected .zip or .docm attachment by tempting subject lines, such as the following:

• Please, see the attachment;
• To the head of sales;
• Scanned image;
• etc.

Similarly to Bart ransomware, this virtual infection attempts to deceive users into executing a JavaScript file or enabled macros. Once it's done, it encodes files with RSA-2048 and AES-128 ciphers. As a result, they get blocked bearing .zepto extension. At the end of the encryption process ^[3],  ransomware changes the desktop picture with an image that presents information about the virus and a request to pay a ransom. If this menace has befallen you, you should still remove Zepto. You might also try this free Zepto Decrypter afterward.

Now the attention might be directed to Lukitus and Ykcol versions, which hide in .7z email attachments. Though the virus was most active at the end of 2016, even now, some companies report getting infected with this version. Since the cyber criminals shuffle Locky variations, it would not be surprising if you can get infected with malware after opening the .7z attachment.

Take into consideration that hackers apply emotional pressure to persuade users to hurry with the payment ^[4]. Likewise, they succeeded in collecting more than $100,000 with the help of  ransomware. Let us assure you that there are ways to complete virus removal. The most effective of them is to use SpyHunterCombo Cleaner or MalwarebytesMalwarebytes security software. Additionally, experts also recommend performing a full system scan with FortectIntego after the elimination to restore the Windows system back to normal.

Like in the previous versions, ransomware activates via the dll file, which is executed by the rundll32.exe file. The latter is a legitimate system process. Likewise, it allows escaping users' intervention. Just as other ransom-demanding viruses, this malware leaves one of the following ransom notes:

• _[2 chars]_HELP_instructions.html
• _[2 chars]_HELP_instructions.txt 

Zepto ransomware states that there is no other way to decrypt files but to pay a ransom and receive a private key and a decryption program. We highly discourage you from purchasing the tool promoted by the perpetrators as it seems a malicious software as well. 

Instructions on how to access payment site are also provided by this virus. During the investigation process, we discovered that the payment site advertises Locky decrypter which was used by another ransomware called Locky. Now it can be purchased for 4 Bitcoins (approximately 2541 USD).

Of course, you should never think of that because you can be left without both, your files and your money. To recover your data, you should remove ransomware first and then restore your files from a backup. Take a look at the ransom note by the virus: 

!!! IMPORTANT INFORMATION !!!!

All of your files are encrypted with RSA-2048 and AES-128 ciphers.
More information about the RSA and AES can be found here:
hxxps://en.wikipedia.org/wiki/RSA_(cryptosystem)
hxxps://en.wikipedia.org/wiki/Advanced_Encryption_Standard

Decrypting of your files is only possible with the private key and decrypt program, which is on our secret server.
To receive your private key follow one of the links:

If all of this addresses are not available, follow these steps:
1. Download and install Tor Browser:
2. After a successful installation, run the browser and wait for initialization.
3. Type in the address bar:
4. Follow the instructions on the site.

After Locky rampaged in the virtual world for a couple of months, soon afterward, the cyber campaign of Zepto was launched. It reached its peak in July. Ordinary and corporate users all around the world were assaulted by ransomware. Thus, even if you reside in Sweden^[5], which is regarded as the country with the lowest malware rate, stay vigilant.

As previously mentioned, the threat employs a swift [XXX|XXXX].js file for a disguise. By pretending to be a financial report or invoice, it captures victims' attention. Opening the attachment enables ransomware to start its mischief in thousands of computers. After sending HTTP GET requests, the threat can get important information about victims' computers. This also enables the .zepto file extension virus to infect a larger amount of computers.

By planting its wscript.exe executable ^[6] among the registry files, ransomware keeps the device in its claws even if you reboot it. Moreover, the virus has been updated to such an extent that even Windows Defender fails to block it. Therefore, it is of crucial importance that your security applications are updated daily.

Moreover, ODIN ransomware appeared as a backup to the original version of the threat. It seems that the felons do not intend to step aside.

Criminals keep releasing updates of the crypto-malware

Despite all the new variants of Locky ransomware, the Zepto virus is still detected spreading worldwide. Researchers note that this file-encrypting cyber threat reached its distribution peak of 150% from July to September in 2017. Nonetheless, since then, though the spam campaign of this particular version subsided slightly, IT specialists spot its variations once in a while. The recent version disguised under the luainstall.dll file. It also disguised under the following names:

• UFDFcTFN2.dll.3904.dr;
• LPwBHJjO2.dll;
• nvFjEHFele2.dllCrTqhHDO3.dll;
• BsTVXmdKk1.dll;
• 3_FILE.exe
• oqmCxkcjyFG1.dll^[7].

Malware actively targets European countries, the United States, South America, and East Asian regions. Lately, virus researchers spotted that Locky ransomware, as well as its newest version – .aesir file extension virus, stepped on Facebook. Malware started spreading via Facebook’s messages by sending a malicious SVG image file. Victims, who clicked on it, were redirected to a suspicious domain that looked like YouTube.

However, they were asked to install the plugin to play the video. This bogus plugin is Nemucod Trojan which is responsible for activating malware on the affected computer. Malware analysts expect ransomware to spread on Facebook or other social networks as well. Therefore, chances to encounter this cyber menace remain high. The only free and safe data recovery solution is backups.

The peculiarities of the original Locky ransomware

The precursor of ransomware, known as Locky virus, has numerous versions which are regularly released in the cyberspace. The original version of the file-encrypting virus was first discovered in February. Attackers keep upgrading the malware to ensure that decryption tools by security firms would be disabled. Additionally, the updates help to improve the security of cybercriminals and help them remain anonymous. 

Zepto is not as advanced as its previous version. However, security experts have already started making the virus decryption tool which should be quite similar to Locky decrypter and should show up anytime soon. This virus was, and still is, one of the most powerful ransomware variants and none of the malware researchers attempts’ to create a decryption tool for it were successful.

Unfortunately, it seems that these cybercriminals know what they are doing, and they do take advantage of their programming skills because their malicious programs appear to be uncrackable. If you are reading this article and your computer is not infected yet, please follow these rules to protect your computer from this ransomware and avoid a need to deal with removal:

• Install anti-malware software on your computer to keep it protected from malicious viruses;
• Keep all your software up-to-date. Our tip is to enable automatic updates;
• BACK UP your files. In fact, this is the only way to secure your data from encryption. You have to create file copies and save them on a removable storage drive, and then unplug it from your computer. You can use backups in case your computer gets hit by ransomware;
• Never open suspicious emails or files attached to them! Cybercriminals distribute this virus by sending deceptive letters to thousands of email accounts, claiming that they deliver invoices, phone bills, speeding tickets, CV, or similar documents.

Ransomware spreads similarly to other cyber threats

This dangerous file-encrypting virus is distributed using well-known tactics — malicious spam emails which are holding deceptive attachments. Usually, the bogus scripts are embedded into .zip or .docm files. Hackers also employ social engineering methods to disguise the payload of the ransomware under innocent-looking file names.

Such malicious code can be activated via Word Macros function or by launching a JavaScript file, so make sure you don’t do that in case you see a scrambled text after opening a Word document that you have received via email.

Criminals also send JS files, which can be activated just by opening them. Also, though such a method is not widely practiced, but beware of exploit kits. They might be trojans, rogue malware, or any malignant files.

By passing themselves off as legitimate files, they might slip into the system and then launch ransomware when the time comes. In order to decrease the possibility of such a malware attack, do not forget to update your security applications daily.

In general, we recommend you to avoid clicking or opening any kind of content online if you are not sure if it is secure. Cybercriminals use numerous techniques to deceive computer users, and it can be hard to keep up with the news and know all sources of infection.

We advise you to protect your computer with anti-malware software, backup your data, and refrain from opening emails sent from strangers. For more information about ceasing Zepto file hijack, take a look at this article — How to protect your computer from Locky? 5 tips for taking control.

Use an official decryption software for data recovery

Users who want to remove ransomware should keep in mind that this cyber threat is highly dangerous. Not only it can trick you into uninstalling essential system files, but also let other malicious programs inside your computer. Thus, follow the instructions to get rid of this file-encrypting virus safely. 

Removal requires advanced IT knowledge. Likewise, we recommend you to get help from professional antivirus tools, like SpyHunterCombo Cleaner or MalwarebytesMalwarebytes. They are designed to identify and locate all ransomware-related components to clean your entire computer system. To ensure that the machine runs just as well as prior to the infection and all the Windows system files are intact again, scan the device with FortectIntego.

Once you get rid of ransomware, you will be able to proceed to data recovery. You can decrypt files with the .zepto extension using an official decryption tool. It is presented at the end of this article alongside alternative solutions to retrieve compromised information.