Zepto virus: .zepto file extension decryptor By Will Wisser Posted on June 29, 2016 3 min read 0 6,080 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. Skewed files with the .zepto extension 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 _HELP_instructions.bmp image 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. Zepto ransomware automated removal and data recovery 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 Download Zepto virus remover 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. 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 Stellar Data Recovery features this type of a capability and therefore it can be applied in ransom attack scenarios to at least get the most important files back. So use the app to get an idea of what data can be restored and let it do the recovery job. Here is a step-by-step walkthrough: 1. Download and install Stellar Data Recovery. Download Stellar Data Recovery 2. Open the application, select the types of recoverable files to look for, and click Next. 3. Choose the areas you want the tool to recover from and click the Scan button. 4. Having scanned the specified locations, the program will display a notification about the total amount of recoverable data. Close the dialog and click the Recover button. This will hopefully help you get some of your valuable files back. Ransomware Prevention Tips To avoid Zepto ransomware and other file-encrypting infections in the future, follow several simple recommendations: Toggle your email provider’s anti-spam settings to filter out all the potentially harmful incoming messages. Raising the bar beyond the default protection is an important countermeasure for ransom TrojansDefine specific file extension restrictions in your email system. Make sure that attachments with the following extensions are blacklisted: .js, .vbs, .docm, .hta, .exe, .cmd, .scr, and .bat. Also, treat ZIP archives in received messages with extreme cautionRename the vssadmin.exe process so that ransomware is unable to obliterate all Shadow Volume Copies of your files in one shotKeep your Firewall active at all times. It can prevent crypto ransomware from communicating with its C&C server. This way, the threat won’t be able to obtain cryptographic keys and lock your filesBack up your files regularly, at least the most important ones. This recommendation is self-explanatory. A ransomware attack isn’t an issue as long as you keep unaffected copies of your data in a safe placeUse an effective antimalware suite. There are security tools that identify ransomware-specific behavior and block the infection before it can do any harm. These techniques are certainly not a cure-all, but they will add an extra layer of ransomware protection to your security setup. 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. Another benefit of using the antimalware tool is that it will keep ransomware threats from intruding on your computer further on. Download Zepto ransomware removal tool
Locky ransomware evolution There are ransomware samples out there whose devs cannot boast professional data encryption practices, …