LDHY Virus (.ldhy File): How to Decrypt & Remove Ransomware?

The Ldhy virus, known as a ransomware infection, is part of the STOP family. This malware is famous for its malicious file encryption capabilities. When the Ldhy virus infects a computer, it scans the system for files like videos, photos, documents, and more. It modifies the file structure and appends the “.ldhy” extension to each encrypted file, making them inaccessible and unusable without the decryption.

Ldhy Virus Overview

Ldhy

🤔 Ldhy malware belongs to ransomware that originates from the DJVU/STOP ransomware family. Its primary purpose is to cipher all of your files it can reach. Then, the ransomware virus asks to pay the ransom – ($499 – $999) in Bitcoin.

The Ldhy virus is a malicious program that encrypts your files and coerces you into paying for their recovery. This ransomware encrypts a wide selection of file types. Encrypted files can be identified by a distinct “.ldhy” extension. As a result, the files touched by ransomware become inaccessible and unusable.

After that, the ransomware asks for a ransom payment in Bitcoin from the victims, which ranges from $499 to $999, depending on the time passed after the attack. Typically, a ransom text file is named as “_readme.txt“.

Ldhy Ransomware operates by Salsa20 encryption algorithms to cipher the targeted files. Since Ldhy virus utilizes such a robust encryption method, it becomes really hard, if even possible, to find the decryption key without cooperating with the attackers.

Once Ldhy malware finishes the encryption, it shows a ransom note to the user, asking for a ransom payment in exchange for the decryption key. The ransom note contains instructions on the ways of making the payment and often includes threats of data loss or increased ransom amounts if the ransom is not paid within a specified timeframe.

I have compiled an all-encompassing list of the solutions, tips, and approaches to neutralize the Ldhy ransomware and recover access to your files. There are situations when it may be possible to restore your files, while sometimes, it may be impossible.

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📌 Important Note!

It is critical to say that paying off the ransom does not guarantee the successful files recovery. The cybercriminals behind the Ldhy virus are known for their untrustworthiness. There were cases where people have paid the ransom, only to be denied by the cyber criminals with the decryption key provision.

Ldhy uses a unique key for each victim, with one exception:

If Ldhy fails to connect the command and control server (C2) before starting the encryption process, it uses offline keys. An offline key is the same for all users, which allows for the decryption of files encrypted by the ransomware.

The Ldhy virus is highly similar to other DJVU ransomware variants such as Lkhy, Cdxx, Wisz, Cdtt, and Lkfr. This virus encrypts a wide range of common file types and appends its distinct “.ldhy” extension to all files. For instance, a file named “1.jpg” would be altered to “1.jpg.ldhy” and “2.png” to “2.png.ldhy“.

Upon successful encryption, the virus creates a special text file named “_readme.txt” and places it in every folder containing the encrypted files. It also adds the readme file to the desktop, so the user will not miss its appearance even without opening folders.

The image below provides a visual representation of files with the “ldhy” extension:

Encrypted Files by STOP/DJVU Ransomware

Name	Ldhy Virus
Ransomware family¹	DJVU/STOP² ransomware
Extension	.ldhy
Ransomware note	_readme.txt
Ransom	From $499 to $999 (in Bitcoins)
Contact	[email protected], [email protected]
Symptoms	Installs password-stealing Trojan on the system, like Vidar Stealer or RedLine Stealer; Adds a list of domains to the HOSTS file to block access to certain security-related sites; Encrypts most of your files (photos, videos, documents) and adds a particular “.ldhy” extension; Manages to install a SmokeLoader backdoor; Can delete Volume Shadow copies to make victim’s attempts to restore data impossible;
Fix Tool	To remove possible malware infections, scan your PC: 6-day free trial available.

The frightening warning demanding users to pay the ransom to unlock the encrypted data contains these exasperating warnings:

_readme.txt (STOP/DJVU Ransomware) – This message asks for payment to restore files via decryption key.[/caption>

Ldhy ransomware performs a set of operations that execute certain activities on a victim’s computer. One of the first operations launched is winupdate.exe, a deceptive process that displays a fake Windows update notification during the attack. This trick helps convince the victim that a sudden PC slowdown is caused by a Windows update.

Simultaneously, the ransomware runs another process (named 4 random chars) which initiates scanning the PC for target files and ciphering them. Then the ransomware deletes Volume Shadow Copies from the disk using the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once erased, it becomes virtually impossible to recover the previous computer state using System Restore Points. The problem is, that ransomware operators are getting rid of any built-in Windows techniques that could aid the victim to regain files for free. In addition, the crooks modify the Windows HOSTS file by including a list of domains to it and directing them to the localhost IP. As a result, the victim will encounter a DNS_PROBE_FINISHED_NXDOMAIN error when trying to open one of the listed websites.

We’ve observed that ransomware endeavors to block websites that promote various how-to guides for computer users. It is obvious that by limiting specific domains, the crooks are attempting to prevent the victim from connecting to relevant and helpful ransomware-attack-related information online. This malware also keeps two .txt files on the victim’s computer that offer information related to the attack – the public key of this victim and personal ID. These two files are named bowsakkdestx.txt and PersonalID.txt.

After all these changes, the malware doesn’t stop. Variants of STOP/DJVU tend to deploy Vidar password-stealing Trojan on compromised systems. This threat carries an extensive list of capabilities, including:

Gathering sensitive data by running malicious software on the victim’s computer.
Acquiring unauthorized login credentials of Steam, Telegram, and Skype accounts.
Manipulating and viewing files on the victim’s computer without their knowledge.
Stealing cryptocurrency wallets from the victim’s system.
Granting the hackers remote control over the victim’s computer for various malicious activities.
Extracting sensitive information such as browser cookies, saved passwords, and browsing history.

The cryptography algorithm used by the DJVU/STOP virus is AES-256. So, if your data got encrypted with an online decryption key, the possibility of getting your files back is quite low. The thing is, the online key is unique for each victim, and brute forcing will take too much time.

Retrieving the online key in any other way is also nearly impossible. It is kept on a remote server controlled by the criminals who spread the Ldhy malware. For receiving the unlocking key the payment should be $999. To obtain the payment details, the victims should contact the hackers by email ([email protected]).

The message by the ransomware states the following information:

ATTENTION!

Don't worry, you can return all your files!
All your files like pictures, databases, documents, and other important are encrypted with the strongest encryption and unique key.
The only method of recovering files is to purchase a decrypt tool and a unique key for you.
This software will decrypt all your encrypted files.
What guarantees do you have?
You can send one of your encrypted files from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. The file must not contain valuable information.
Do not ask assistants from YouTube and recovery data sites for help in recovering your data.
They can use your free decryption quota and scam you.
Our contact is emails in this text document only.
You can get and look video overview decrypt tool:
https://we.tl/t-hPAqznkJKD
The price of private key and decrypt software is $999.
A discount of 50% is available if you contact us first 72 hours, that's the price for you is $499.
Please note that you'll never restore your data without payment.
Check your e-mail "Spam" or "Junk" folder if you don't get an answer for more than 6 hours.


To get this software you need to write to our e-mail:
[email protected]

Reserve an e-mail address to contact us:
[email protected]

Your personal ID:

Your personal ID:
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

How To Remove STOP/Djvu Ransomware?

Video Guide

How To Decrypt .ldhy Files?

How to restore big files?

Try deleting .ldhy extension on a few big files and opening them. This malware has issues with large file encryption. Either the virus scanned and did not lock the file, or it bugged and did not add the filemarker. If you have very large files (2GB+), such a situation is highly probable. Please, let me know in the comments if that will work for you.

The newest extensions were released around the end of August 2019 after the criminals made changes. This includes Cdcc, Cdxx, Cdtt etc.

As a result of the changes made by the criminals, STOPDecrypter is no longer supported. It has been replaced with the Emsisoft Decryptor for STOP Djvu Ransomware developed by Emsisoft.

You can download free decryption tool here: Decryptor for STOP Djvu.

Select folders for decryption.

Based on the default configurations, the decryptor will automatically choose the accessible directories to decrypt the currently accessible drives (the connected ones), including the network drives. You can choose other locations with the “Add” button.

Decryptors typically offer several options considering the specific malware family. The present possible options are shown in the Options tab and can be activated or disabled there. You may discover a detailed list of the currently active Options below.

Click on the “Decrypt” button.

As soon as you add all the desired locations for decryption to the list, click on the “Decrypt” button to initiate the decryption procedure.

Note that the main screen may turn you to a status view, letting you know of the active process and the decryption statistics of your data:

The decryptor will notify you as soon as the decryption procedure is completed. If you need the report for your papers, you can save it by choosing the “Save log” button. Note that it is also possible to copy it directly to your clipboard and paste it into emails or messages here if you need to do so.

The Emsisoft Decryptor might display different messages after a failed attempt to restore your files:

✓ Error: Unable to decrypt a file with ID: [your ID]

Emsisoft does not have a corresponding key in the database.

✓ No key for New Variant online ID: [your ID]

Notice: this ID appears to be an online ID, decryption is impossible

Malware uses an online key to cipher your files. Your key is unique and is kept on the command server, controlled by criminals. File recovery without paying the ransom is impossible. 🙁

✓ Result: No key for new variant offline ID: [example ID]

This ID appears to be an offline ID. Decryption may be possible in the future.

An offline key was used, but files could not be restored (the offline decryption key isn’t available yet). But, this message is good news for you, because it is possible to restore your files in the future. 🙂

It can take a few weeks or months until the decryption key gets found and uploaded to the decryptor. Please follow updates regarding the decryptable DJVU versions here.

✓ Remote name could not be resolved

This stands for a DNS issue. Consider resetting your HOSTS file to default.

How to Restore .ldhy Files?

In some cases ransomware is not doom for your files…

The Ldhy ransomware encryption algorithm is next: it encodes every file byte-by-byte, then saves a file copy, removing (not overriding!) the original file. Hence, the data of the file placement on the physical disk is lost, but the original file is not removed from the disk. The cell, or the sector where this file was kept, can still hold this file, but it is not present in the file system and can be overwritten by data that has been loaded to this drive after the deletion. Hence, it is possible to restore your files using special software.

I recently had my PC infected by this virus. It managed to bypass 2 Antivirus software and 2 malware fighters.

Anyway, after realizing it was an online algorithm, it was impossible to retrieve my encrypted files. I also had my backup drive plugged in at the time of the virus, and this was also infected, or so I thought. Every folder within my backup drive had been infected and was encrypted. However, despite losing some important files, I retrieved almost 80% of my 2TB storage.

When I started going through the folders, I noticed the readme.txt ransom note in every folder. I opened some of the folders and found that all files that were not in a subfolder within that folder had been encrypted. However, I found a flaw and a glimmer of hope when I went into the subfolders in other folders and found that these files had not been encrypted. Every folder within my c and d drives, including subfolders, had been encrypted, but this was not the case with the backup drive. Having subfolders created within a folder has saved 80% of my data.

As I said, I believe this to be only a small loophole on a backup drive. I’ve since found a further 10 % of my data on another hard drive on a different PC. So my advice is if you use a backup drive, create subfolders. I was lucky, I guess. But I was also unlucky that the virus hit as I was transferring some files from my backup.

Hopefully, this can help others in my situation.

Jamie Newland

Some pointers for recovery repair of Ldhy files (true for all STOP/DJVU variants):

I have seen Stop/Djvu variants fail to encrypt deeper nested folders, so you can check that. You may find those are not encrypted.

This ransomware saves encrypted data to a new file and deletes the original. So there’s a slight chance part of that deleted file can be recovered using file recovery software. It’s unlikely the folder structure can be restored, so a free tool like PhotoRec may be as good as any.

This ransomware only partially encrypts (about the first 150 KB), so depending on file size and type of data, the non-encrypted part may be recoverable.

Joep

Recovering your files with PhotoRec

PhotoRec is a free open-source program, which is initially created for data recovery from damaged disks, or files recovery in case they are unintentionally deleted. However, as time has gone by, this program adopted the ability to restore the files of 400 different extensions. Hence, it can be used for file recovery after the Ldhy attack.

First, you need to download this app. It is 100% free, but the developer states that there is no assurance that your files will be recovered. PhotoRec is distributed together with another program of the same developer – TestDisk. The program archive will have a TestDisk name but don’t worry. PhotoRec files are right inside.

To run PhotoRec, you need to find and open “qphotorec_win.exe” file. No setup is needed – the program has all the files it needs inside of the archive, hence, you can fit it on your USB drive, and help your friends/parents/anyone who has been attacked by Ldhy ransomware.

After the launch, you will observe the screen showing you the complete list of your disks. However, this data is probably unhelpful, because the required menu is a bit higher. Click this menu, then choose the disk which was attacked by ransomware.

After choosing the disk, you need to opt for the destination folder for the reclaimed files. This menu is located at the lower part of the PhotoRec window. The best option is to export them on a USB drive or any other type of removable disk.

Then, you need to define the file formats. This choice is located at the bottom, too. As mentioned, PhotoRec can regain the files in about 400 different formats.

Finally, you can begin file restoration by pressing the “Search” button. You will view the screen where the results of the scan and recovery are shown.

Ldhy files recovery Video Guide.

Frequently Asked Questions

🤔 How can I open “.ldhy” files?

No way. These files are encrypted by ransomware. The contents of encrypted files are not available until they are decrypted.

🤔 This virus has blocked the infected PC: I can’t get the activation code.

In this situation, you need to prepare the memory stick with a pre-installed

🤔 Decryptor did not decrypt all my files, or not all of them were decrypted. What should I do?

Have patience. You are infected with the new version of STOP/DJVU ransomware, and decryption keys have not yet been released. Follow the news on our website. We will keep you posted when new keys or new decryption programs appear.

🤔 What can I do right now?

The Ldhy ransomware encrypts only the first 150KB of files. So MP3 files are rather large, some media players (Winamp for example) may be able to play the files, but – the first 3-5 seconds (the encrypted portion) will be missing. You can try to find a copy of an original file that was encrypted: Files you downloaded from the Internet that were encrypted and you can download again to get the original.

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Brendan Smith