S_Fusion.exe – How to Remove It [Fix]

What is S_Fusion.exe?

S_Fusion.exe appeared in your Task Manager, your antivirus flagged it, or it is consuming CPU or network resources you cannot account for. Read this article right now before doing anything, then follow the fix guide below — the identification step matters significantly here before any removal action is taken.

S_Fusion.exe is a suspicious process name that needs to be evaluated by its file path and context before being treated as confirmed malware or dismissed as legitimate. The “S_” prefix is a naming pattern used by some malware and adware components to create the impression of a Windows service executable — since Windows services frequently use prefixes like “S_” or “Svc” to signal their service identity, a malicious file using this convention can blend into Task Manager alongside legitimate system processes. The Fusion-related naming space has documented malware associations: Malwarebytes classifies Adware.FusionCore as a large family of adware bundlers targeting Windows systems, and Microsoft’s threat database includes both Trojan:Win32/FusionCore and Trojan:Win32/FusionDrive detections. A process named S_Fusion.exe running from outside any expected software installation directory — particularly from AppData, Temp, or a random folder — should be treated as malicious and investigated immediately.

How Did I Get S_Fusion.exe?

Suspicious processes in the Fusion-related naming space typically arrive through these documented routes:

• Software bundling with free downloads from unofficial sources — The most consistent delivery route for adware and PUP components in the FusionCore family: a free program downloaded from a third-party site includes the adware component as a bundled addition through software bundling, installing silently alongside the expected application during setup.
• Pirated software or cracked application installers — Cracked software packages from torrent or unofficial distribution sites frequently include adware and Trojan components embedded in the installer that run automatically during setup.
• A fake update or download prompt during browsing — A pop-up from an ad-heavy or compromised site claiming a browser or media player update is required can deliver a package containing S_Fusion.exe alongside or instead of any legitimate update.
• A malicious email attachment or drive-by download — A document or archive received through email or downloaded from a disreputable site can execute a dropper that installs the process onto the system.

What Does S_Fusion.exe Do?

The behavior depends on which category the process belongs to. Here is the full picture based on the documented Fusion-related malware family and the general behavior of processes using service-masking naming:

• Adware behavior: injects ads and generates redirects — If the process belongs to the FusionCore adware family, its primary function is to inject advertisements into browser sessions, generate malicious redirects, and collect browsing data through embedded trackers for data collection and ad-revenue purposes.
• Trojan behavior: opens the system to further payloads — If the process is a Trojan variant using the Fusion naming convention, it may function as a dropper or backdoor, opening the system to additional malware injection and potentially harvesting credentials, session cookies, and saved browser passwords.
• Uses the S_ prefix to evade scrutiny — The service-masking naming convention is specifically chosen to make the process appear as a legitimate Windows or application service in Task Manager, reducing the chance that a user performing a manual investigation will terminate or investigate it further.
• Persists through scheduled tasks or startup entries — Malware processes using service-masking names typically establish registry key entries, scheduled tasks, or startup entries to ensure the process restarts after deletion or system reboot, meaning simply ending the Task Manager process will not remove it permanently.

How to identify which version you have: Right-click S_Fusion.exe in Task Manager and select “Open File Location.” If the path is inside a recognized software installation directory for a program you deliberately installed — and the file is digitally signed by a known publisher — it may be legitimate. If the path is in AppData, Temp, a random subfolder, or any location you do not recognize, treat it as malicious immediately. Submit the file to VirusTotal for multi-engine verification if you are uncertain.

What Should You Do?

Do not simply end the process in Task Manager without also addressing its startup mechanism — the process will restart on the next reboot if the underlying installation component is not removed. Start by verifying the file path as described above. If it is in an unexpected location, boot into Safe Mode (press F8 or hold Shift while clicking Restart) to prevent the process from loading, then run a full scan with a dedicated anti-malware tool to identify and remove all associated components, scheduled tasks, and registry entries. Check Task Scheduler (taskschd.msc) for any task pointing to S_Fusion.exe or an unfamiliar script, and check the Startup tab in Task Manager for any entry associated with the process. If a scan finds Trojan-related components, change all passwords from a clean device and enable 2FA on all accounts before using any of them from the affected machine. Follow the complete fix guide below this article for the full step-by-step removal process on Windows.

Ventsislav Krastev

Ventsislav is a cybersecurity expert at SensorsTechForum since 2015. He has been researching, covering, helping victims with the latest malware infections plus testing and reviewing software and the newest tech developments. Having graduated Marketing as well, Ventsislav also has passion for learning new shifts and innovations in cybersecurity that become game changers. After studying Value Chain Management, Network Administration and Computer Administration of System Applications, he found his true calling within the cybersecrurity industry and is a strong believer in the education of every user towards online safety and security.

More Posts - Website

Follow Me:

---

Preparation before removing S_Fusion.exe.

Before starting the actual removal process, we recommend that you do the following preparation steps.

• Make sure you have these instructions always open and in front of your eyes.
• Do a backup of all of your files, even if they could be damaged. You should back up your data with a cloud backup solution and insure your files against any type of loss, even from the most severe threats.
• Be patient as this could take a while.

• Scan for Malware
• Fix Registries
• Remove Virus Files

Step 1: Scan for S_Fusion.exe with SpyHunter Anti-Malware Tool

1. Click on the "Download" button to proceed to SpyHunter's download page.

Download

Malware Removal Tool

---

It is recommended to run a scan before purchasing the full version of the software to make sure that the current version of the malware can be detected by SpyHunter. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria.

---

2. After you have installed SpyHunter, wait for it to update automatically.

---

3. After the update process has finished, click on the 'Malware/PC Scan' tab. A new window will appear. Click on 'Start Scan'.

---

4. After SpyHunter has finished scanning your PC for any files of the associated threat and found them, you can try to get them removed automatically and permanently by clicking on the 'Next' button.

If any threats have been removed, it is highly recommended to restart your PC.

Step 2: Clean any registries, created by S_Fusion.exe on your computer.

The usually targeted registries of Windows machines are the following:

• HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
• HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
• HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
• HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce

You can access them by opening the Windows registry editor and deleting any values, created by S_Fusion.exe there. This can happen by following the steps underneath:

---

1. Open the Run Window again, type "regedit" and click OK.

---

2. When you open it, you can freely navigate to the Run and RunOnce keys, whose locations are shown above.

---

3. You can remove the value of the virus by right-clicking on it and removing it. Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.

Step 3: Find virus files created by S_Fusion.exe on your PC.

1.For Windows 8, 8.1 and 10.

For Newer Windows Operating Systems

1: On your keyboard press  + R and write explorer.exe in the Run text box and then click on the Ok button.

2: Click on your PC from the quick access bar. This is usually an icon with a monitor and its name is either “My Computer”, “My PC” or “This PC” or whatever you have named it.

3: Navigate to the search box in the top-right of your PC's screen and type “fileextension:” and after which type the file extension. If you are looking for malicious executables, an example may be "fileextension:exe". After doing that, leave a space and type the file name you believe the malware has created. Here is how it may appear if your file has been found:

N.B. We recommend to wait for the green loading bar in the navigation box to fill up in case the PC is looking for the file and hasn't found it yet.

2.For Windows XP, Vista, and 7.

For Older Windows Operating Systems

In older Windows OS's the conventional approach should be the effective one:

1: Click on the Start Menu icon (usually on your bottom-left) and then choose the Search preference.

2: After the search window appears, choose More Advanced Options from the search assistant box. Another way is by clicking on All Files and Folders.

3: After that type the name of the file you are looking for and click on the Search button. This might take some time after which results will appear. If you have found the malicious file, you may copy or open its location by right-clicking on it.

Now you should be able to discover any file on Windows as long as it is on your hard drive and is not concealed via special software.

S_Fusion.exe FAQ

What Does S_Fusion.exe Trojan Do?

The S_Fusion.exe Trojan is a malicious computer program designed to disrupt, damage, or gain unauthorized access to a computer system. It can be used to steal sensitive data, gain control over a system, or launch other malicious activities.

Can Trojans Steal Passwords?

Yes, Trojans, like S_Fusion.exe, can steal passwords. These malicious programs are designed to gain access to a user's computer, spy on victims and steal sensitive information such as banking details and passwords.

Can S_Fusion.exe Trojan Hide Itself?

Yes, it can. A Trojan can use various techniques to mask itself, including rootkits, encryption, and obfuscation, to hide from security scanners and evade detection.

Can a Trojan be Removed by Factory Reset?

Yes, a Trojan can be removed by factory resetting your device. This is because it will restore the device to its original state, eliminating any malicious software that may have been installed. Bear in mind that there are more sophisticated Trojans that leave backdoors and reinfect even after a factory reset.

Can S_Fusion.exe Trojan Infect WiFi?

Yes, it is possible for a Trojan to infect WiFi networks. When a user connects to the infected network, the Trojan can spread to other connected devices and can access sensitive information on the network.

Can Trojans Be Deleted?

Yes, Trojans can be deleted. This is typically done by running a powerful anti-virus or anti-malware program that is designed to detect and remove malicious files. In some cases, manual deletion of the Trojan may also be necessary.

Can Trojans Steal Files?

Yes, Trojans can steal files if they are installed on a computer. This is done by allowing the malware author or user to gain access to the computer and then steal the files stored on it.

Which Anti-Malware Can Remove Trojans?

Anti-malware programs such as SpyHunter are capable of scanning for and removing Trojans from your computer. It is important to keep your anti-malware up to date and regularly scan your system for any malicious software.

Can Trojans Infect USB?

Yes, Trojans can infect USB devices. USB Trojans typically spread through malicious files downloaded from the internet or shared via email, allowing the hacker to gain access to a user's confidential data.

About the S_Fusion.exe Research

The content we publish on SensorsTechForum.com, this S_Fusion.exe how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific trojan problem.

How did we conduct the research on S_Fusion.exe?

Please note that our research is based on an independent investigation. We are in contact with independent security researchers, thanks to which we receive daily updates on the latest malware definitions, including the various types of trojans (backdoor, downloader, infostealer, ransom, etc.)

Furthermore, the research behind the S_Fusion.exe threat is backed with VirusTotal.

To better understand the threat posed by trojans, please refer to the following articles which provide knowledgeable details.