The SYSDF Ransomware Virus – What You Need to Know

SYSDF is a variant of the notorious Dharma ransomware family that has been actively infecting victims globally. Like others in the Dharma group, SYSDF uses strong encryption to lock files on compromised systems and demands ransom payments for decryption keys.

This article provides an in-depth look at the SYSDF ransomware – how it works, its unique characteristics, the damage it can cause, and most importantly, what you need to know to protect yourself or recover if infected. Read on to learn everything about this malicious threat.

Overview of the SYSDF Ransomware

SYSDF is a dangerous ransomware variant that encrypts files on infected systems and demands ransom payments in bitcoin to decrypt them. Part of the notorious Dharma family, SYSDF utilizes strong encryption algorithms to lock documents, photos, databases, backups, and other critical files.

This ransomware appends the .z1n extension to encrypted files along with a unique victim ID and the attacker’s email address. It leaves ransom notes in every directory naming the email addresses to contact for payment.

SYSDF disables antivirus tools and deletes Volume Shadow Copies to block recovery options. Infection often occurs through phishing emails, compromised RDP access, drive-by downloads, and unpatched software exploits.

Some key features of the SYSDF ransomware include:

Encrypts a Broad Range of File Types

One of the hallmarks of SYSDF is its broad targeting of files for encryption across both local drives and connected network shares. Personal user files like documents, spreadsheets, photos, music and video files are encrypted. But SYSDF doesn’t stop there. It will also encrypt critical system files, databases, backups, and more.

For example, database files from programs like MySQL and MongoDB have been locked, as well as backup files created by software such as Veeam and Commvault. Entire network shares of data can be encrypted. This indiscriminate approach leads to maximum damage.

Appends ID, Email and Extension to Files

A common tactic used by SYSDF is appending the original filename with a unique victim identification string, the attacker’s email address, and the .z1n extension.

For example, a file named “familyphoto.jpg” would become “familyphoto.jpg.[uniqueID].[attacker@email].z1n”. This renaming takes place before the encryption process begins.

The attackers can use the ID value to distinguish different victims. And the email address provides a way for victims to make contact for payment.

Leaves Ransom Notes in Text Files

After encrypting files in a given directory, SYSDF leaves behind a ransom note named “read.txt” in the same folder. This text file contains brief instructions to contact the attackers via email to supposedly obtain decryption.

The language used in the note encourages urgency and implies that paying the ransom is the only way to get files back.

For example, a SYSDF ransom note may contain:

All your files have been encrypted!


Don’t worry, you can return all your files!
If you want to restore them, write to the mail: Dec24hepl@aol.com YOUR ID [removed]If you have not answered by mail within 12 hours, write to us by another mail: [removed]


We strongly recommend that you do not use the services of intermediaries and first check the prices and conditions directly with us.


The use of intermediaries may involve risks such as:
-Overcharging: Intermediaries may charge inflated prices, resulting in improper additional costs to you.

-Unjustified debit: There is a risk that your money may be stolen by intermediaries for personal use and they may claim that we did it.


-Rejection of the transaction and termination of communication: Intermediaries may refuse to cooperate for personal reasons, which may result in termination of communication and make it difficult to resolve issues.


We understand that data loss can be a critical issue, and we are proud to provide you with encrypted data recovery services. We strive to provide you with the highest level of confidence in our abilities and offer the following guarantees:
—Recovery demo: We provide the ability to decrypt up to three files up to 5 MB in size on a demo basis.

Please note that these files should not contain important and critical data.


Demo recovery is intended to demonstrate our skills and capabilities.


—Guaranteed Quality: We promise that when we undertake your data recovery, we will work with the utmost professionalism and attention to detail to ensure the best possible results.


We use advanced technology and techniques to maximize the likelihood of a successful recovery.


—Transparent communication: Our team is always available to answer your questions and provide you with up-to-date information about the data recovery process.


We appreciate your participation and feedback.


Attention!
Do not rename encrypted files.
Do not try to decrypt your data using third party software, it may cause permanent data loss.
Decryption of your files with the help of third parties may cause increased price (they add their fee to our) or you can become a victim of a scam.

By leaving these notes across an infected system, the attackers hope to pressure and panic victims into paying.

May Attempt Deleting Volume Shadow Copies

Some variants of the SYSDF ransomware attempt to escalate privileges and delete Volume Shadow Copy backups and system restore points from the infected Windows system.

For example, the command “vssadmin delete shadows /all /quiet” might be executed to wipe volume shadow copies. This prevents victims from utilizing these automated system backups to recover encrypted files.

However, the ransomware does not always succeed in gaining admin privileges necessary to carry out this deletion. When possible, SYSDF will attempt to block this recovery option.

Avoids Wasting Effort on Poor Regions

An interesting aspect of SYSDF is its use of geo-IP location tracking to identify the physical region an infected system is operating from.

Using this data, the ransomware is programmed to avoid encrypting files and demanding payment if the victim is located in a poorer region where ransoms are less likely to be paid.

For example, if a system in the developing world is infected, SYSDF may exit without encrypting to avoid wasting effort. Geo-targeting allows the attackers to maximize profits.

Disables Windows Defender and Firewall

To enable persistence, SYSDF also leverages various techniques like adding a run registry key to ensure the ransomware re-executes after a system reboot.

But it goes further – SYSDF attempts to disable the native Windows Defender antivirus or firewall to prevent these protections from detecting the ransomware activity or preventing the malicious processes from communicating with command and control servers.

With an overview of how SYSDF operates, signatures to watch for, and its technical capabilities, defenders gain an advantage in catching these ransomware attacks before they can inflict major harm. Understanding your enemy is the first step toward defeating them.

SYSDF Ransomware Threat Summary

Threat DetailsDescription
NameSYSDF Ransomware
TypeRansomware
File Extension.z1n (Appended with ID and Email)
Ransom NotePop-up and read.txt Files
Decryptor availableNo
Contact EmailsDec24hepl@aol.com, zohodzin@cock.li
Detection NamesTrojan.Ransom.Crysis.E, Trojan-Ransom.Win32.Crusis.to, Ransom-Dharma!187085F60A15, Win32:RansomX-gen [Ransom], TR/Dropper.Gen, A Variant Of Win32/Filecoder.Crysis.P, Ransom:Win32/Wadhrama!pz, Win32.Trojan-Ransom.VirusEncoder.A
SymptomsEncrypted Files, Changed Extensions, Ransom Demands
DistributionEmail Spam, Malvertising, Compromised Sites
DamageFull Encryption of Files, Lost Access

The SYSDF ransomware encrypts files on infected systems and appends the .z1n extension along with a unique victim ID. A ransom note is displayed demanding payment in Bitcoin to receive decryption keys. SYSDF spreads through tactics like phishing emails, drive-by downloads, and exploiting unpatched software vulnerabilities. Infection can result in total data loss without recovery options, underscoring the importance of prevention, detection, and backup.

How the SYSDF Ransomware Infects Systems

Now that we’ve covered a high-level overview, let’s look at how the SYSDF ransomware typically manages to get onto systems in the first place.

The most common SYSDF attack vectors include:

Phishing Emails

Fake emails containing infected attachments or links to malicious sites are a prime vector. The emails pretend to be invoices, deliveries, or important notifications to tempt victims.

Compromised Remote Desktop Access

Unsecured RDP ports allow attackers to remotely connect and manually deliver the payload. Brute force attacks on weak RDP passwords are common.

Software Vulnerabilities

Unpatched apps/OS with critical remote code execution flaws can be exploited to download and install SYSDF without any action by the victim.

Malicious Downloads

Fake installers, cracks/keygens, or pirated software often bundle SYSDF ransomware code without the user’s knowledge.

Malvertising and Scam Sites

Malicious ads or pop-ups that redirect to SYSDF download pages can infect those who click without realizing the risks.

As we can see, SYSDF employs a variety of social engineering, configuration oversight, unpatched software, and user security awareness gaps to ultimately compromise targets.

Now let’s look at the specific steps SYSDF takes once on a system to encrypt files and extort victims.

How the SYSDF Ransomware Encryption Process Works

When executed on a system, SYSDF ransomware follows a precise process to encrypt data. Understanding how this plays out step-by-step is critical to detecting and interrupting an attack:

1. Kill Processes Holding Files Open

SYSDF terminates any processes with open file handles, like database servers or document editing programs. This ensures these files aren’t locked when encryption starts.

2. Enumerate Drives and Shares

The ransomware scans across local hard drives and mapped network shares to build a list of targets for encryption. Home directories and shared storage are not off limits.

3. Check for Existing Encryption

SYSDF checks each file against an included list of file extensions already encrypted by other ransomware strains. Any matches are excluded from encryption to avoid wasting time.

4. Append File Names with ID and Extension

Before encrypting a file, SYSDF appends the unique victim ID, attacker email, and “.z1n” extension to the filename. This renaming takes place in preparation of encryption.

5. Encrypt Files with Strong Algorithm

Next, SYSDF encrypts files using a robust algorithm like AES-256 or RSA-2048. A securely generated key is used to encrypt each file, which is different per victim.

6. Delete Volume Shadow Copies

If possible, SYSDF seeks out and deletes Volume Shadow Copy backups on the system to block recovery options.

7. Drop Ransom Note in All Directories

SYSDF drops a ransom note named “read.txt” in every folder where files were encrypted. This contains payment instructions.

8. Change Wallpaper to Ransom Note

Finally, SYSDF sets the desktop wallpaper to an image bearing a ransom payment note for visibility.

This sequence highlights the methodical and comprehensive steps SYSDF takes to encrypt files and pressure victims. But understanding this pattern is also incredibly useful for detecting SYSDF mid-attack.

Detecting an Ongoing SYSDF Ransomware Attack

Detecting a SYSDF ransomware attack as quickly as possible, before significant encryption takes place, can make recovery much easier.

Here are key signals that may indicate SYSDF is encrypting files:

  • Running processes like “dharma.exe”, “accepteula.exe” or similar
  • High disk I/O activity as files are encrypted
  • Changed file extensions appending ID, email, and “.z1n”
  • Deletion of volume shadow copies and restore points
  • Presence of “read.txt” ransom notes in folders
  • Changed desktop background to ransom note image

Aggressively monitoring endpoints for these indicators can help uncover a SYSDF attack in the early stages when less damage has occurred. But prevention is always preferable to detection.

Preventing SYSDF Ransomware Infections

The most effective way to deal with SYSDF is to prevent it from ever compromising systems in the first place. Here are proactive measures to protect against infection:

  • Patch software vulnerabilities – Unpatched apps and operating systems are often targeted as an initial infection vector. Prompt patching prevents exploitation.
  • Block malicious email attachments/links – Advanced email security tools can analyze attachments and links in real-time to catch phishing attempts.
  • Secure RDP access – Brute force attacks leverage weak RDP passwords. Require strong credentials and limit source IPs for remote access.
  • Install robust endpoint protection – Anti-malware tools with behavioral analysis capabilities can block processes associated with ransomware activity.
  • Backup critical data – Maintain recent backups offline and immutable to allow recovery of encrypted files without paying the ransom.
  • Restrict execution permissions – Limiting normal user execution permissions makes it harder for malware payloads to execute.
  • User security training – Educate staff to identify social engineering techniques, safely handle emails/downloads, and report anomalies.

Combining layers of technical defenses with user education offers the best protection against rapidly evolving malware like SYSDF.

What to Do If You Become Infected with SYSDF Ransomware

Even with proactive measures, ransomware attacks can still slip past defenses. So what should you do if you discover SYSDF has encrypted your files?

1. Isolate the Infected System

First, disconnect the compromised device from any networks or shared storage to prevent SYSDF from spreading. This limits the potential impact.

2. Determine the Scope of Encryption

Conduct triage to assess the amount of encryption that has taken place across endpoints and file shares. This helps understand the severity and prioritize recovery of critical assets first.

3. Check for a Decryptor

Research whether any free decryption tools have been released that can unlock files encrypted by the specific SYSDF variant you are dealing with. These occasionally become available through security researchers.

4. Restore Files from Backup

If viable backups exist and were not compromised by SYSDF, restore encrypted files from unencrypted versions in backup storage. Ensure backups are intact first.

5. Consult Incident Response Experts

For extensive infections, leverage professional incident response teams to provide technical analysis and strategize the recovery process. They may have additional options.

6. Report the Incident

File a report with the FBI’s Internet Crime Complaint Center (IC3) and your local authorities. Provide event details, ransom note, bitcoin wallet, etc. This supports law enforcement tracking ransomware attackers.

7. Don’t Pay the Ransom

Unless absolutely necessary, avoid paying the ransom. There is no guarantee you’ll get decryption keys, and it encourages more attacks. Focus on restoration from backups instead.

With the proper response plan, the damage and disruption caused by threats like SYSDF ransomware can be minimized.

Remove the SYSDF ransomware and recover the files

It’s important to understand that by starting the removal process you risk losing your files, as we cannot guarantee that you will be able to recover them. Your files may be permanently compromised when trying to remove this infection or trying to recover the encrypted documents.
We cannot be held responsible for losing your files or documents during this removal process.

It’s recommended to create a backup image of the encrypted drives or files before proceeding with the malware removal instructions so that you can restore them if the decryption keys are recovered from the cybercriminals’ servers. To create a backup for your encrypted files or drives, you can use EaseUS Todo Backup Free.

This malware removal guide may appear overwhelming due to the number of steps and numerous programs that are being used. We have only written it this way to provide clear, detailed, and easy-to-understand instructions that anyone can use to remove malware for free.
Please perform all the steps in the correct order. If you have any questions or doubts at any point, stop and ask for our assistance.
To remove the SYSDF ransomware, follow these steps:

STEP 1: Start your computer in Safe Mode with Networking

In this first step, we will start your computer in Safe Mode with Networking to prevent SYSDF malicious drivers and services from loading at Windows start-up. We’re using Safe mode because it starts Windows in a basic state, using a limited set of files and drivers.

Windows 11Windows 10Windows 7
Before you enter Safe Mode, you need to enter the Windows Recovery Environment (winRE). To do this, follow the below steps:

  1. Press Windows logo key + I on your keyboard to open Settings. If that doesn’t work, right-click on the Start button, then select Settings. In the right window, click on Recovery.
    Go to Windows Settings
  2. Under Advanced startup, select Restart now.
    Recovery window in Windows 10

Now that you are in Windows Recovery Environment, you will follow these steps to take you to safe mode:

  1. On the Choose an option screen, select “Troubleshoot“.
    Windows 11 - Start in Safe Mode with Network
  2. On the “Troubleshoot” screen, click the “Advanced Options” button.
    Windows 11 - Start in Safe Mode with Network - Step 2
  3. On the “Advanced Options” page, click the “Startup Settings” option.
    Windows 11 - Start in Safe Mode with Network - Step 3
  4. On the “Startup Settings” page, click the “Restart”.
    Windows 11 - Start in Safe Mode with Network - Step 4
  5. After your device restarts, you’ll see a list of options. Select option 5 from the list or press F5 to enter Safe Mode with Networking.
    Boot in Safe Mode Windows 11
  6. While your computer is running in Safe Mode with Networking, we will need to download, install and run a scan with Malwarebytes (explained in Step 2).
Before you enter Safe Mode, you need to enter the Windows Recovery Environment (winRE). To do this, follow the below steps:

  1. Press the Windows logo key + I on your keyboard to open Settings. If that doesn’t work, select the Start button, then select Settings.
    Go to Windows Settings
  2. When the Windows Settings window opens, select Update & Security, then click on Recovery.
    Recovery window in Windows 10
  3. Under Advanced startup, select Restart now.
    Open Advance Startup

Now that you are in Windows Recovery Environment, you will follow these steps to take you to safe mode:

  1. On the Choose an option screen, select “Troubleshoot“.
    Windows 10 - Start in Safe Mode with Network
  2. On the “Troubleshoot” screen, click the “Advanced Options” button.
    Windows 10 - Start in Safe Mode with Network - Step 2
  3. On the “Advanced Options” page, click the “Startup Settings” option. In Windows 8, this option is labeled “Windows Startup Settings” instead.
    Windows 10 - Start in Safe Mode with Network - Step 3
  4. On the “Startup Settings” page, click the “Restart”.
    Windows 10 - Start in Safe Mode with Network - Step 4
  5. After your device restarts, you’ll see a list of options. Select option 5 from the list or press F5 to enter Safe Mode with Networking.
    Boot in Safe Mode Windows 10
  6. While your computer is running in Safe Mode with Networking, we will need to download, install and run a scan with Malwarebytes (explained in Step 2).
  1. Remove all floppy disks, CDs, and DVDs from your computer, and then restart your computer.
  2. When the computer starts you will see your computer’s hardware being listed. When you see this information start to press the F8 key repeatedly until you are presented with the Advanced Boot Options.
    F8 Safe Mode
  3. In the Advanced Boot Options screen, use the arrow keys to highlight Safe Mode with Networking and then press Enter.
    Safe Mode with Networking screen
  4. While your computer is running in Safe Mode with Networking, we will need to download, install and run a scan with Malwarebytes (explained in Step 2). In some cases, victims may have issues while trying to start the computer in Safe Mode with Networking, if this happens, you can try to scan your computer with Malwarebytes in normal mode.

STEP 2: Use Malwarebytes to remove SYSDF ransomware

While the computer is in Safe Mode with Networking, we will download, install and run a system scan with Malwarebytes.

Malwarebytes stands out as one of the leading and widely-used anti-malware solutions for Windows, and for good reason. It effectively eradicates various types of malware that other programs often overlook, all at no cost to you. When it comes to disinfecting an infected device, Malwarebytes has consistently been a free and indispensable tool in the battle against malware. We highly recommend it for maintaining a clean and secure system.

  1. Download Malwarebytes for Windows

    You can download Malwarebytes by clicking the link below.

    MALWAREBYTES FOR WINDOWS DOWNLOAD LINK
    (The above link will open a new page from where you can download Malwarebytes)
  2.  

    Install Malwarebytes

    After the download is complete, locate the MBSetup file, typically found in your Downloads folder. Double-click on the MBSetup file to begin the installation of Malwarebytes on your computer. If a User Account Control pop-up appears, click “Yes” to continue the Malwarebytes installation.

    MBAM1
  3. Follow the On-Screen Prompts to Install Malwarebytes

    When the Malwarebytes installation begins, the setup wizard will guide you through the process.

    • You’ll first be prompted to choose the type of computer you’re installing the program on—select either “Personal Computer” or “Work Computer” as appropriate, then click on Next.

      MBAM3 1
    • Malwarebytes will now begin the installation process on your device.

      MBAM4
    • When the Malwarebytes installation is complete, the program will automatically open to the “Welcome to Malwarebytes” screen.

      MBAM6 1
    • On the final screen, simply click on the Open Malwarebytes option to start the program.

      MBAM5 1
  4. Enable “Rootkit scanning”.

    Malwarebytes Anti-Malware will now start, and you will see the main screen as shown below. To maximize Malwarebytes’ ability to detect malware and unwanted programs, we need to enable rootkit scanning. Click on the “Settings” gear icon located on the left of the screen to access the general settings section.

    MBAM8

    In the settings menu, enable the “Scan for rootkits” option by clicking the toggle switch until it turns blue.

    MBAM9

    Now that you have enabled rootkit scanning, click on the “Dashboard” button in the left pane to get back to the main screen.

  5. Perform a Scan with Malwarebytes.

    To start a scan, click the Scan button. Malwarebytes will automatically update its antivirus database and begin scanning your computer for malicious programs.

    MBAM10
  6. Wait for the Malwarebytes scan to complete.

    Malwarebytes will now scan your computer for browser hijackers and other malicious programs. This process can take a few minutes, so we suggest you do something else and periodically check the status of the scan to see when it is finished.

    MBAM11
  7. Quarantine detected malware

    Once the Malwarebytes scan is complete, it will display a list of detected malware, adware, and potentially unwanted programs. To effectively remove these threats, click the “Quarantine” button.

    MBAM12

    Malwarebytes will now delete all of the files and registry keys and add them to the program’s quarantine.

    MBAM13

  8. Restart your computer.

    When removing files, Malwarebytes may require a reboot to fully eliminate some threats. If you see a message indicating that a reboot is needed, please allow it. Once your computer has restarted and you are logged back in, you can continue with the remaining steps.

    MBAM14

When the malware removal process is complete, your computer should start in normal mode (if not, simply restart your device to exit Safe Mode) and continue with the rest of the instructions. We do recommend that you run another scan with Malwarebytes once you’re in Normal mode to make sure all the malicious files were removed.


STEP 3: Use HitmanPro to scan for Trojans and other malware

In this third step, while the computer is in normal back, we will download and run a scan with HitmanPro to remove the SYSDF ransomware and other malicious programs.

HitmanPro is a second-opinion scanner that takes a unique cloud-based approach to malware scanning. HitmanPro scans the behavior of active files and also files in locations where malware normally resides for suspicious activity. If it finds a suspicious file that’s not already known, HitmanPro sends it to its clouds to be scanned by two of the best antivirus engines today, which are Bitdefender and Kaspersky.

Although HitmanPro is shareware and costs $24.95 for 1 year on 1 PC, there is no limit on scanning. The limitation only kicks in when there is a need to remove or quarantine detected malware by HitmanPro on your system and by then, you can activate the one-time 30-days trial to enable the cleanup.

  1. Download HitmanPro.

    You can download HitmanPro by clicking the link below.

    HITMANPRO DOWNLOAD LINK
    (The above link will open a new web page from where you can download HitmanPro)
  2. Install HitmanPro.

    When HitmanPro has finished downloading, double-click on “hitmanpro.exe” (for 32-bit versions of Windows) or “hitmanpro_x64.exe” (for 64-bit versions of Windows) to install this program on your computer. In most cases, downloaded files are saved to the Downloads folder.

    Double-click on the HitmanPro file

    You may be presented with a User Account Control pop-up asking if you want to allow HitmanPro to make changes to your device. If this happens, you should click “Yes” to continue with the installation.

    Windows asking for permissions to run the HitmanPro setup

  3. Follow the on-screen prompts.

    When HitmanPro starts you will be presented with the start screen as shown below. Click on the “Next” button to perform a system scan.

    Click Next to install HitmanPro on your PC

    HitmanPro final installer screen

  4. Wait for the HitmanPro scan to complete.

    HitmanPro will now begin to scan your computer for malicious programs.
    HitmanPro scans your computer for any infections, adware, or potentially unwanted programs that may be present

  5. Click on “Next”.

    When HitmanPro has finished the scan, it will display a list of all the malware that it has found. Click on the “Next” button to have HitmanPro remove the detected items.

    HitmanPro scan summary. Click Next to remove malware

  6. Click on “Activate free license”.

    HitmanPro may now require to activate the free 30-days trial to remove the malicious files. To do this, click on the “Activate free license” button to begin the free 30 days trial and remove all the malicious files from your computer.
    Click on the Activate free license button

    When the malware removal process is complete, it will display a screen that shows the status of the various programs that were removed. At this screen, you should click on the Next button and then if prompted you should click on the Reboot button. If HitmanPro does not prompt you to reboot, please just click on the Close button.


STEP 4: Double-check for malicious programs with ESET Online Scanner

In this fourth step, we run a scan with ESET Online Scanner to remove any leftover files from the SYSDF ransomware and other malicious programs.

ESET Online Scanner is a free second-opinion scanner, designed to rescue your computer from malware (viruses, trojans, rootkits, etc.) that have infected your computer despite all the security measures you have taken (such as anti-virus software, firewalls, etc.).

  1. Download ESET Online Scanner.

    You can download ESET Online Scanner by clicking the link below.

    ESET ONLINE SCANNER DOWNLOAD LINK

    (The above link will open a new web page from where you can download ESET Online Scanner)
  2. Double-click on esetonlinescanner.exe to run the installer.

    When ESET Online Scanner has finished downloading, double-click on “esetonlinescanner.exe” to install it program on your computer. In most cases, downloaded files are saved to the Downloads folder.
    Image - Double-click on the ESET Online Scanner setup file

  3. Install ESET Online Scanner.

    When ESET Online Scanner starts you will be presented with the start screen as shown below. Select your desired language from the drop-down menu and click Get started.

    Image - Click Get Started to install ESET Online Scanner

    In the Terms of use screen, click Accept.
    Image - Accept Terms to Install ESET Online Scanner

    Select your preference for the Customer Experience Improvement Program and the Detection feedback system and click Continue.
    Image - Follow the on-screen prompts

  4. Start a Full Scan with ESET Online Scanner

    Click on Full Scan to perform an in-depth inspection of the entire computer.

    Start a Full Scan with ESET Online Scanner

    Select Enable for Detection of Potentially Unwanted Applications, then click Start scan.

    Image - Enable PUA Detection and Start Scan

  5. Wait for the ESET Online Scanner scan to finish.

    ESET Online Scanner will now begin to scan your computer for malware. This process can take quite a while, so we suggest you do something else and periodically check on the status of the scan to see when it is finished.

    Image- Wait for the ESET Online Scanner scan to finish

  6. ESET Online Scanner will automatically remove the malicious files.

    At the end of the scan, the Found and resolved detections screen will be displayed. You can click View detailed results to view specific information. Detected threats are automatically cleaned and quarantined.
    Image - ESET Online Scanner malware removal


STEP 5: Restore the files encrypted by the SYSDF ransomware

Unfortunately, in most cases, it’s not possible to recover the files encrypted by this ransomware virus because the private key which is needed to unlock the encrypted files is only available through the attackers. However, below we’ve listed three options you can use to try and recover your files.

Make sure you remove the malware from your computer first, otherwise, it will repeatedly lock your system or encrypt files. If you suspect that your computer is still infected with malware, you can run a free scan with Emsisoft Emergency Kit.

Option 1: Search a decryption tool for this ransomware

The cybersecurity community is constantly working to create ransomware decryption tools, so you can try to search these sites for updates:

Option 2: Use EaseUS Data Recovery Wizard Free to recover the encrypted files

EaseUS Data Recovery Wizard Free can restore files and repair corrupted files with simple clicks. Its powerful scanning algorithms can identify and retrieve huge file type library, including all of the popular video files, audio files, photos, and document formats.
While the free version only allows you to recover 2 GB of data, this can be helpful to see if the recovery is possible and restore back the most important files from your computer.

  1. Download EaseUS Data Recovery Wizard Free.

    You can download EaseUS Data Recovery Wizard Free by clicking the link below.

    EASEUS DATA RECOVERY WIZARD FREE DOWNLOAD LINK

    (The above link will open a new page from where you can download EaseUS Data Recovery Wizard)
  2. Double-click on the EaseUS Data Recovery Wizard Free setup file.

    When EaseUS Data Recovery Wizard Free has finished downloading, double-click on the setup file to install EaseUS Data Recovery Wizard on your computer. In most cases, downloaded files are saved to the Downloads folder.

    Image: EaseUS Data Recovery Wizard Free Installer

    You may be presented with a User Account Control pop-up asking if you want to allow EaseUS to make changes to your device. If this happens, you should click “Yes” to continue with the EaseUS Data Recovery Wizard Free installation.

  3. Follow the on-screen prompts to install EaseUS Data Recovery Wizard.

    When the EaseUS Data Recovery Wizard installation begins, click on the “Install Now” as seen in the image below.
    EaseUS Data Recovery Wizard Free Install Now

    When your EaseUS Data Recovery Wizard installation completes, click the “Start Now” button to start the program.
    Image: Click Start Now

  4. Select a location to start recovering the encrypted files.

    Choose the drive or folder where you are the encrypted files that you want to recover and click “Scan“.
    Select a location to start recovering the encrypted files

  5. Wait for the EaseUS Data Recovery Wizard scan to complete.

    EaseUS Data Recovery Wizard will now scan your computer files that can be restored. This process can take a few minutes, so we suggest you do something else and periodically check on the status of the scan to see when it is finished.
    Image: Wait for the EaseUS Data Recovery Wizard scan to complete.

  6. Find the files you want to recover.

    When the EaseUS Data Recovery Wizard scan is finished scanning it will show a screen that displays the files that can be recovered. This tool can recover a lot of data, use the “Filter” button to quickly filter specific file types and find the files that you want to recover.
    Filter the Files by Type

    Click the “Preview” button or double-click on a file for a full preview.
    Image: Click Preview to view the file

  7. Select your files and click “Recover”.

    Finally, select the the files you want to recover and click “Recover“.
    Select your files and click Recover
    Choose a safe location to save all the files.
    Select a safe location
    The free version only allow you to recover 2 GB of data, however, this will allow you to recover the most important files and see if EaseUS Data Recovery Wizard can correctly recover them.
    Image: View Recovered Files

Option 3: Try to restore your files with ShadowExplorer

This ransomware will attempt to delete all shadow copies when you first start any executable on your computer after becoming infected. Thankfully, the infection is not always able to remove the shadow copies, so you should continue to try restoring your files using this method.

  1. Download ShadowExplorer.

    You can download ShadowExplorer from the below link.

    SHADOW EXPLORER DOWNLOAD LINK
    (This link will open a new web page from where you can download “ShadowExplorer”)
  2. Install ShadowExplorer.

    Double-click on the ShadowExplorer-x.x-setup file to start the installation process, then follow the on-screen promts to install this program.
    Install Shadow Defender

  3. Select snapshot date.

    Open ShadowExplorer and then from the top bar select the drive where the files that you want to save are located, then select from the snapshot available one previous to this infection.

    Select drive and date to recover the files encrypted by this ransomware

  4. Export the files that you want to recover.

    Once you have found a copy of the original file or folder, right-click on it and the select “Export”. A window will prompt you where you want to save the file or folder.
    Find copy then click on Expor to recover the files encrypted by this ransomware

Your computer should now be free of the SYSDF ransomware infection and other malware.

If your current antivirus allowed this malicious program on your computer, you may want to consider purchasing the full-featured version of Malwarebytes Anti-Malware to protect against these types of threats in the future.
If you are still having problems with your computer after completing these instructions, then please follow one of the steps:

Frequently Asked Questions About the SYSDF Ransomware

1. What is the SYSDF ransomware?

SYSDF is a dangerous ransomware variant in the Dharma family known for encrypting files on compromised systems. It appends the .z1n extension and ransom note to encrypted files and demands payment for decryption keys. SYSDF utilizes strong encryption algorithms and also deletes Volume Shadow Copies to block recovery.

2. How does the SYSDF ransomware infect systems?

SYSDF leverages various infection vectors like phishing emails, brute force RDP attacks, software exploits, malvertising campaigns, and compromised software downloads. Social engineering is used heavily to trick users into enabling its installation.

3. What types of files does SYSDF ransomware encrypt?

SYSDF encrypts a broad range including documents, media files, databases, backups, network shares, and critical system files. This indiscriminate approach maximizes damage and leverage over victims.

4. How can I tell if SYSDF ransomware is encrypting my system?

Signs like files appended with ID and .z1n, ransom notes in each folder, changed desktop backgrounds, disabling of antivirus, and deletion of shadow copies may indicate SYSDF activity. Rapid detection can limit damage.

5. Should I pay the ransom if infected with SYSDF?

No, we strongly advise against paying the ransom. There is no guarantee you will receive working decryption keys in return, and it encourages more ransomware attacks. Restore from backups instead.

6. How can I recover encrypted files without paying the ransom?

Having a recent, offline data backup that SYSDF did not compromise allows you to restore encrypted files. You can also check if any free decryptors have been released to unlock files encrypted by the specific SYSDF variant.

7. Can antivirus or firewalls block the SYSDF ransomware?

Antivirus with behavioral analysis and firewalls can potentially detect and block processes associated with SYSDF activity. However multiple layers of security are ideal, since threats are constantly evolving.

8. Is there any way to decrypt .z1n encrypted files without the key?

No unfortunately the strong encryption used by SYSDF essentially makes files unrecoverable without the attacker’s unique decryption key. This is why preventing infection is so crucial.

9. Who is responsible for creating and spreading SYSDF ransomware?

The origins are unclear but cybercriminal groups and state-sponsored actors have been tied to similar ransomware strains. The decentralized nature makes attribution difficult. Global law enforcement is investigating.

10. How can I improve my defenses against ransomware like SYSDF?

Keeping software patched, securing RDP access, filtering email attachments/links, training staff on threats, segmenting networks, and maintaining offline backups are key best practices against ransomware attacks.

The Bottom Line

The SYSDF ransomware and its variants represent a dangerous threat capable of inflicting tremendous damage due to its robust encryption tactics, multi-pronged infection methods, and global reach.

However, by understanding SYSDF’s core behaviors and technical capabilities covered in this article, organizations are empowered to detect potential attacks early and implement layered defenses to significantly lower the risk.

The key takeaways include:

  • SYSDF utilizes social engineering, software exploits, supply chain compromise, and RDP brute forcing to infiltrate systems.
  • The ransomware encrypts local drives, networks shares, backups, databases, and critical files.
  • Warning signs like changed file extensions, ransom notes, and shadow copy deletion can signal SYSDF activity.
  • Preventive controls like patch management, email security, tight RDP access, endpoint protection, and user education provide protection.
  • Offline, immutable backups allow restoration of encrypted data without paying ransoms.
  • Quick isolation, scoping the infection, and contacting experts are key incident response steps.

By putting these lessons into action, individuals and organizations can bolster their resilience against ransomware while depriving attackers of illicit profits. Vigilance and preparation are our best defenses against malware like SYSDF.

How to Stay Safe Online

Here are 10 basic security tips to help you avoid malware and protect your device:

  1. Use a good antivirus and keep it up-to-date.

    Shield Guide

    It's essential to use a good quality antivirus and keep it up-to-date to stay ahead of the latest cyber threats. We are huge fans of Malwarebytes Premium and use it on all of our devices, including Windows and Mac computers as well as our mobile devices. Malwarebytes sits beside your traditional antivirus, filling in any gaps in its defenses, and providing extra protection against sneakier security threats.

  2. Keep software and operating systems up-to-date.

    updates-guide

    Keep your operating system and apps up to date. Whenever an update is released for your device, download and install it right away. These updates often include security fixes, vulnerability patches, and other necessary maintenance.

  3. Be careful when installing programs and apps.

    install guide

    Pay close attention to installation screens and license agreements when installing software. Custom or advanced installation options will often disclose any third-party software that is also being installed. Take great care in every stage of the process and make sure you know what it is you're agreeing to before you click "Next."

  4. Install an ad blocker.

    Ad Blocker

    Use a browser-based content blocker, like AdGuard. Content blockers help stop malicious ads, Trojans, phishing, and other undesirable content that an antivirus product alone may not stop.

  5. Be careful what you download.

    Trojan Horse

    A top goal of cybercriminals is to trick you into downloading malware—programs or apps that carry malware or try to steal information. This malware can be disguised as an app: anything from a popular game to something that checks traffic or the weather.

  6. Be alert for people trying to trick you.

    warning sign

    Whether it's your email, phone, messenger, or other applications, always be alert and on guard for someone trying to trick you into clicking on links or replying to messages. Remember that it's easy to spoof phone numbers, so a familiar name or number doesn't make messages more trustworthy.

  7. Back up your data.

    backup sign

    Back up your data frequently and check that your backup data can be restored. You can do this manually on an external HDD/USB stick, or automatically using backup software. This is also the best way to counter ransomware. Never connect the backup drive to a computer if you suspect that the computer is infected with malware.

  8. Choose strong passwords.

    lock sign

    Use strong and unique passwords for each of your accounts. Avoid using personal information or easily guessable words in your passwords. Enable two-factor authentication (2FA) on your accounts whenever possible.

  9. Be careful where you click.

    cursor sign

    Be cautious when clicking on links or downloading attachments from unknown sources. These could potentially contain malware or phishing scams.

  10. Don't use pirated software.

    Shady Guide

    Avoid using Peer-to-Peer (P2P) file-sharing programs, keygens, cracks, and other pirated software that can often compromise your data, privacy, or both.

To avoid potential dangers on the internet, it's important to follow these 10 basic safety rules. By doing so, you can protect yourself from many of the unpleasant surprises that can arise when using the web.

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