Csharp-Streamer is a RAT (Remote Access Trojan) that has been around since at least 2020. There are multiple versions of this malware, and evidence suggests that Csharp-Streamer is modular.

RATs enable remote access and control over infected devices. Csharp-Streamer has been utilized in numerous attacks, including several different ransomware infections.

Csharp-Streamer malware overview

As a RAT (Remote Access Trojan), Csharp-Streamer is designed to allow remote access/control over machines. These trojans tend to be highly versatile, and the multiple variants of Csharp-Streamer imply that it is a modular malware. In other words, this trojan may be customized between attacks by utilizing various modules. Hence, the capabilities exhibited by this malicious program can be incredibly varied.

In one of the known Csharp-Streamer infections, this RAT relied on a broad set of PowerShell scripts to carry out its malicious activities. Some of the notable features used by this version included browsing, searching, and exfiltrating files. It also had the ability to take screenshots and record keystrokes (keylogging). Csharp-Streamer used password brute-forcing as well.

As mentioned in the introduction, this trojan was leveraged in ransomware attacks. The following data-encrypting ransomware was utilized in said infections – Sodinokibi (aka REvil, Sodin), ALPHV (BlackCat), and Metaencryptor. The attackers behind the latter have shown particular interest in targeting IT service providers.

It is noteworthy that ransomware attacks leveraged against large entities often involve double extortion tactics, wherein victims are threatened with data leaks if they fail to comply with the cyber criminals' demands. Sensitive information can be obtained using malware like Csharp-Streamer or by relying on additional stealers.

It must be mentioned that malware developers/attackers commonly improve upon their software and methodologies. It is even more likely that future attacks involving Csharp-Streamer will have additional/different functionalities or features, as this RAT is modular.

To summarize, the presence of software like Csharp-Streamer on devices can result in multiple system infections, data loss, severe privacy issues, financial losses, and identity theft. It is pertinent to mention that malware leveraged against high-sensitivity targets can pose threats of even greater significance.

Threat Summary:

Name	Csharp-Streamer remote access trojan
Threat Type	Trojan, RAT, Remote Access Trojan, Remote Administration Tool, password-stealing virus.
Detection Names	Avast (Win64:DropperX-gen [Drp]), Combo Cleaner (IL:Trojan.MSILZilla.6459), ESET-NOD32 (A Variant Of MSIL/SharpS.I), Kaspersky (HEUR:Trojan.MSIL.Agent.gen), Microsoft (HEUR:Trojan.MSIL.Agent.gen), Full List Of Detections (VirusTotal)
Payload	Sodinokibi (aka REvil, Sodin), ALPHV (BlackCat), Metaencryptor
Symptoms	Trojans are designed to stealthily infiltrate the victim's computer and remain silent, and thus no particular symptoms are clearly visible on an infected machine.
Distribution methods	Infected email attachments, malicious online advertisements, social engineering, software 'cracks'.
Damage	Stolen passwords and banking information, identity theft, the victim's computer added to a botnet.
Malware Removal (Mac)	To eliminate possible malware infections, scan your Mac with legitimate antivirus software. Our security researchers recommend using Combo Cleaner. To use full-featured product, you have to purchase a license for Combo Cleaner. Limited seven days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

Remote access trojan examples

We have written thousands of articles on malware; AllaSenha, NiceRAT, SHARPIL, Narnia, and VCURMS are just some of our latest on RATs. Trojans of this kind can have a wide variety of capabilities and even allow for near-user-level control over infected devices.

However, regardless of how versatile a piece of malicious software is – its presence endangers system and user safety. Therefore, it is essential to eliminate all threats immediately upon detection.

How did Csharp-Streamer infiltrate my computer?

In the Csharp-Streamer attacks preceding Metaencryptor ransomware infections, this RAT was infiltrated into systems by a PowerShell loader. Additionally, the remote access trojan can self-spread via local networks. However, other techniques are likely used by Csharp-Streamer to infect devices and by attackers to distribute it.

In general, cyber criminals rely on phishing and social engineering to proliferate malware. Malicious software is typically presented as or bundled with ordinary content. Infectious files come in various formats, e.g., executables (.exe, .run, etc.), archives (RAR, ZIP, etc.), documents (PDF, Microsoft Office, Microsoft OneNote, etc.), JavaScript, and so forth.

Malware is primarily spread via loader/backdoor-type trojans, drive-by (stealthy/deceptive) downloads, malicious attachments/links in spam (e.g., emails, PMs/DMs, SMSes, social media posts, etc.), online scams, malvertising, untrustworthy download channels (e.g., unofficial and free file-hosting sites, Peer-to-Peer sharing networks, etc.), pirated programs/media, illegal software activation tools ("cracks"), and fake updates.

Another self-proliferation technique used by malicious programs is spreading through removable storage devices (e.g., external hard drives, USB flash drives, etc.).

How to avoid installation of malware?

We strongly recommend exercising caution with incoming emails, PMs/DMs, SMSes, and other messages. Attachments or links in suspicious/irrelevant mail must not be opened, as they can be virulent. It is just as important to be vigilant while browsing, as fraudulent and malicious online content usually appears genuine and harmless.

Furthermore, all downloads must be performed from official and verified sources. Another recommendation is to activate and update software using functions/tools provided by legitimate developers, as those acquired from third-parties may contain malware.

It is paramount for device integrity and user safety to have a reputable anti-virus installed and kept updated. Security programs must be used to run regular system scans and to remove threats and issues. If you believe that your computer is already infected, we recommend running a scan with Combo Cleaner Antivirus for macOS to automatically eliminate infiltrated malware.

Instant automatic Mac malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of Mac malware. Download it by clicking the button below:
By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. Limited seven days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.

How to remove malware manually?

Manual malware removal is a complicated task - usually it is best to allow antivirus or anti-malware programs to do this automatically. To remove this malware we recommend using Combo Cleaner Antivirus for macOS.

If you wish to remove malware manually, the first step is to identify the name of the malware that you are trying to remove. Here is an example of a suspicious program running on a user's computer:

If you checked the list of programs running on your computer, for example, using task manager, and identified a program that looks suspicious, you should continue with these steps:

Download a program called Autoruns. This program shows auto-start applications, Registry, and file system locations:

Restart your computer into Safe Mode:

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup.

Click the "Restart now" button. Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings".

Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options".

In the advanced options menu select "Startup Settings" and click on the "Restart" button. In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

Video showing how to start Windows 10 in "Safe Mode with Networking":

Extract the downloaded archive and run the Autoruns.exe file.

In the Autoruns application, click "Options" at the top and uncheck "Hide Empty Locations" and "Hide Windows Entries" options. After this procedure, click the "Refresh" icon.

Check the list provided by the Autoruns application and locate the malware file that you want to eliminate.

You should write down its full path and name. Note that some malware hides process names under legitimate Windows process names. At this stage, it is very important to avoid removing system files. After you locate the suspicious program you wish to remove, right click your mouse over its name and choose "Delete".

After removing the malware through the Autoruns application (this ensures that the malware will not run automatically on the next system startup), you should search for the malware name on your computer. Be sure to enable hidden files and folders before proceeding. If you find the filename of the malware, be sure to remove it.

Reboot your computer in normal mode. Following these steps should remove any malware from your computer. Note that manual threat removal requires advanced computer skills. If you do not have these skills, leave malware removal to antivirus and anti-malware programs.

These steps might not work with advanced malware infections. As always it is best to prevent infection than try to remove malware later. To keep your computer safe, install the latest operating system updates and use antivirus software. To be sure your computer is free of malware infections, we recommend scanning it with Combo Cleaner Antivirus for macOS.

Frequently Asked Questions (FAQ)

My computer is infected with Csharp-Streamer malware, should I format my storage device to get rid of it?

Most malware infections can be removed without resorting to such drastic measures.

What are the biggest issues that Csharp-Streamer malware can cause?

The dangers associated with an infection depend on the malware's functionalities and the cyber criminals' modus operandi. Csharp-Streamer enables remote access/control over machines, and it is a modular RAT (i.e., it can be customized using various modules). Hence, the software's capabilities can be incredibly varied. Csharp-Streamer has also been used in ransomware attacks.

Generally, high-risk malware infections can lead to data loss, serious privacy issues, financial losses, and identity theft. Attacks launched against high-sensitivity targets carry even greater risks.

What is the purpose of Csharp-Streamer malware?

Malware is most commonly used for financial gain. However, cyber criminals can also use malicious software to amuse themselves, carry out personal vendettas, disrupt processes (e.g., websites, services, companies, etc.), engage in hacktivism, and launch politically/geopolitically motivated attacks.

How did Csharp-Streamer malware infiltrate my computer?

Csharp-Streamer has been noted infiltrating systems through a PowerShell loader, and it is capable of self-spreading via local networks. However, other infiltration/distribution methods are not unlikely.

In general, malware is proliferated through trojans, drive-by downloads, online scams, spam mail, dubious download sources (e.g., freeware and third-party websites, P2P sharing networks, etc.), malvertising, illegal program activation tools ("cracks"), and fake updates. Aside from local networks, malware may be able to self-spread via removable storage devices.

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner can detect and eliminate all kinds of threats, including most of the known malware infections. It must be stressed that performing a complete system scan is crucial since sophisticated malicious programs typically hide deep within systems.