The tutorial covers a revamped edition of the nasty Locky ransom Trojan, which now appends .zepto extension to ciphered files and extorts 0.5 Bitcoin.
There is hardly any fundamental difference between the previous versions of Locky and the one that surfaced lately. Still, the ransomware attacks Windows PCs through social engineering, encrypts data using a combo of two cryptosystems, and imposes fairly standard recovery steps. The uniqueness of the new strain, however, is out of the question. While substituting the original filenames with 32 random hexadecimal characters, it also puts the .zepto string as the extensions. These items, obviously, are impossible to associate with specific files as they look like a gibberish line of five blocks of symbols separated by hyphens and containing the exact same tail regardless of the initial format.
Another new property of the Zepto virus is the name of ransom instructions. It alerts the contaminated user on the fact of data encryption via the following files: _HELP_instructions.html and _HELP_instructions.bmp, where the name may be preceded by a number. The latter object is an image that automatically replaces the user-defined or default Desktop wallpaper. Essentially, these documents present a file recovery avenue. In particular, the victim is expected to navigate over to a specially crafted “Locky Decryptor” page and use a five-step walkthrough to purchase 0.5 BTC, submit the cryptocurrency to the criminals’ address, wait for the confirmation, and then refresh the page to download the decrypt solution proper.
The strength of encryption standards leveraged for the attack and flawless implementation thereof are the things that prevent ransomware analysts from creating a free .zepto files decryption tool. The infection relies on several layers of encryption. First, it encodes a file with AES (Advanced Encryption Standard), generating a unique key that’s used both for the encoding and decoding routine. Then, it encrypts this key through the use of RSA-2048, a public key cryptosystem. Such a mixture of algorithms is nearly impracticable to defeat, even with significant computational resources on one’s hands.
A reliable way to avoid this ransomware is to refrain from opening email attachments unless there is certainty those are 100% safe. The makers of Crypto viruses mostly employ botnets to generate huge amounts of spam, where they attach contagious files that instantly execute the malicious program if a recipient opens them. Unfortunately, the current detection rate of the Zepto payload by AVs across the board leaves much to be desired.
Paying an equivalent of hundreds of dollars to access what inherently belongs to the user is by all means a disgusting prospect. Before even considering the option of falling for the hackers’ blackmail, be sure to try a couple of effective data recovery practices.
Automated removal of Zepto virus
Owing to an up-to-date database of malware signatures and intelligent behavioral detection, the recommended software can quickly locate the infection, eradicate it and remediate all harmful changes. So go ahead and do the following:
1. Download and install the antimalware tool. Open the solution and have it check your PC for PUPs and other types of malicious software by clicking the Start Computer Scan button
2. Rest assured the scan report will list all items that may harm your operating system. Select the detected entries and click Fix Threats to get the troubleshooting completed.
Ways of non-ransom recovery of .zepto files
Cracking the crypto used by this ransom trojan is more of a science fiction thing rather than an attainable prospect for the masses. This is why the troubleshooting in predicaments of this sort is a matter of two approaches: one is to pay the ransom, which isn’t an option for many victims; and the other is to apply instruments that take advantage of the ransomware’s possible weaknesses. If the latter is your pick, the advice below is a must-try.
Backups can make your day
Not only are you a lucky person in case you’ve been backing up your most important files, but you’re also a wise and prudent user. This isn’t necessarily a resource-heavy activity these days – in fact, some providers of online services are allocating a sufficient size of cloud storage space for free so that every customer can easily upload their critical data without paying a penny. Having removed Zepto ransomware, therefore, all you have to do is download your stuff from the remote server or transfer it all from an external piece of hardware if that’s the case.
Restore previous versions of encrypted files
A positive upshot of using this technique depends on whether or not the ransomware has erased the Volume Shadow Copies of the files on your PC. This is a Windows feature that automatically makes and keeps the backups of data elements on the hard drive as long as System Restore is enabled. The cryptoware in question is programmed to switch off the Volume Shadow Copy Service (VSS), but it has reportedly failed to in some cases. Checking one’s options regarding this workaround is doable in two ways: through the Properties menu of each file or by means of the remarkable open-source tool called Shadow Explorer. We recommend the software-based way because it’s automated, hence faster and easier. Just install the app and use its intuitive controls to get previous versions of the encrypted objects reinstated.
Data recovery toolkit to the rescue
Some strains of ransomware are known to delete the original files after the encryption routine has been completed. As hostile as this activity appears, it can play into your hands. There are applications designed to revive the information that was obliterated because of malfunctioning hardware or due to accidental removal. The tool called Data Recovery Pro by ParetoLogic features this type of capability therefore it can be applied in ransom attack scenarios to at least get the most important files back. So download and install the program, run a scan and let it do its job.
Revise your security status
Post-factum assessment of the accuracy component in malware removal scenarios is a great habit that prevents the comeback of harmful code or replication of its unattended fractions. Make sure you are good to go by running an additional safety checkup.
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