How to remove BitRAT malware from operating systems

What kind of malware is BitRAT?

BitRAT is a malicious program, classified as a Remote Access Trojan (RAT). Malware of this type enables remote access and control over an infected machine. RATs have a wide variety of dangerous functionality. While BitRAT is by far not the most sophisticated piece of malicious software available, nevertheless it is considered highly dangerous.

Therefore, BitRAT infections must be removed immediately upon detection. Since this Trojan is offered for sale by its developers, how it is spread depends on the methods preferred by the cyber criminals who have purchased it.

More about the BitRAT malware

As mentioned, remote access Trojans have a wide variety of malicious features, which can enable varied level of control and misuse of the infected device. These Trojans can gain control over integrated/connected hardware, installed software and content stored in or accessed through the infected computer.

According to BitRAT's promotional material, it is capable of controlling a machine's hardware: employ the device's keyboard and mouse, and possibly move the mouse live/in real-time; via webcams and microphones record video and audio, and stream them live. BitRAT can manage the files stored in the system to a certain degree.

It can exfiltrate and infiltrate (i.e. download and upload) files. The stolen data can then be used for ransom purpose. Furthermore, if the RAT's capability to execute uploaded files is successfully implemented, it may be used to cause chain infections (i.e. to download/install additional malware).

Similarly, BitRAT can stealthily use the browser (hidden/remote browser), specifically the Google Chrome browser. This malicious program can also extract stored log-in credentials (i.e. IDs, usernames and passwords) from browsers and other applications.

The promotional material states that the aforementioned feature of BitRAT is supported on over 35 browsers and more than 500 other different applications. This Trojan has keylogging capabilities.

Thus, it can record key strokes, a feature typically used to collect typed log-in credentials and other vulnerable data (e.g. names, addresses, telephone numbers, emails, banking account and/or credit card details, etc.). The BitRAT can function as a cryptominer as well, and is geared towards mining the Monero (XMR) cryptocurrency.

Whilst BitRAT is a sloppily-constructed malicious program with some of its functionality being nonoperational and detectable, this does not prevent its infections leading to victims experiencing financial loss, serious privacy issues and identity theft.

Therefore, if it is suspected or known that BitRAT (or other malware) has already infected the system, use anti-virus software to eliminate it without delay.

RATs in general

WellMess, DarkCrystal, Imperium Metamorpher, SamoRAT and VenomRAT are some examples of other remote access Trojans.

These types of Trojans have various capabilities, such as data extraction and exfiltration, download/installation of additional malicious programs, spying functionality (video/audio and key stroke recording), cryptocurrency mining, and so on. Regardless of how malware operates, it has just one goal - to generate revenue for the developers and cyber criminals using it.

How did BitRAT infiltrate my computer?

Malware is primarily distributed via spam campaigns, untrusted download channels, illegal activation tools ("cracks") and fake updates. The term "spam campaign" defines a large-scale operation, during which thousands of deceptive/scam emails are sent.

These messages are usually disguised as "official", "important", "urgent", and similar. They contain download links of infectious files and/or the files are simply attached to the emails.

Infectious files can be in various formats (e.g. executables, archives, Microsoft Office and PDF documents, JavaScript, etc.), and when they are opened, the infection process (malware download/installation) is initiated.

Malicious programs are often downloaded unintentionally from dubious download sources such as unofficial and free file-hosting websites, Peer-to-Peer sharing networks and other third party downloaders. Rather than activating licensed products, "cracking" tools can download/install malware.

Fake updaters infect systems by exploiting flaws of outdated products and/or by installing malicious software, rather than the promised updates.

How to avoid installation of malware

Suspicious or irrelevant emails must not be opened, especially those with any links or attachments found in them, as this can result in a system infection. You are advised to use official and trustworthy download channels.

Additionally, all products must be activated and updated with tools/functions provided by legitimate developers, since illegal activation ("cracking") tools and third party updaters are often employed to proliferate malware. To ensure device integrity and user safety, it is paramount to have reputable anti-virus/anti-spyware installed.

Keep this software updated, use it to perform regular system scans and to remove detected threats and issues. If you believe that your computer is already infected, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Screenshot of BitRAT promoted by its developers online:

Example of a malicious Microsoft Excel document used to spread BitRAT malware:

Update January 4, 2023 - Newer and more versatile versions of BitRAT malware have been used to target the customers of an undisclosed Colombian bank. Cyber criminals have managed to obtain the clients' names, national IDs, addresses, payment history, salary data, phone numbers, email addresses, and other sensitive information through a breach of the bank's servers.

The stolen data has been observed being sold on the dark web and used in phishing email campaigns. Using this personal information, criminals can craft convincing fake emails that trick recipients into downloading and opening infectious Microsoft Excel documents, which use malicious macro commands to infect devices with BitRAT.

How to remove malware manually?

Most trojan infections can be removed by running a full system scan with Combo Cleaner. The full manual procedure below is for cases where automatic removal failed, where you want to verify a scan caught everything, or where the threat has multiple persistence points.

Tools you'll need

Combo Cleaner Antivirus 7-days free trial

Recommended primary scanner. VB100 certified. The 7-day free trial is available.

Microsoft Defender Offline Free · built-in

Built into Windows. Boots to a clean environment to catch rootkits.

Process Explorer Free

From Microsoft Sysinternals. Better than Task Manager - shows full paths and signatures.

Autoruns Free

From Microsoft Sysinternals. Lists every place malware can persist on your system.

Microsoft Safety Scanner (MSERT) Free

Official Microsoft on-demand scanner. Always-current signatures - expires every 10 days.

Phase 1~ 5 min

Contain - limit the damage

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1

Disconnect from the network

30 secNo tool needed

Unplug your Ethernet cable and turn off Wi-Fi. If you're on a laptop, the airplane-mode key works fastest.

Why this matters

Many trojans exfiltrate data - saved browser passwords, banking sessions, screenshots - and accept remote commands. Cutting the network stops both immediately. Keep it disconnected until Phase 4.

2

Boot into Safe Mode with Networking

3 min

Safe Mode loads a minimal set of drivers and stops most malware from auto-running. "With Networking" lets you download tools - re-enable Wi-Fi only after you've booted in.

Windows 11

Open Settings → System → Recovery. Click Restart now next to Advanced startup.

Your computer will restart into the "Choose an option" menu. Click Troubleshoot → Advanced options → Startup Settings → Restart. After the second reboot, press 5 or F5.

Windows 10

Click the Windows logo, hold Shift, click the Power icon and choose Restart. In the Choose an option screen, click Troubleshoot → Advanced options → Startup Settings → Restart. Press F5.

Windows 8

Go to the Start Screen, type Advanced, select Settings → Advanced startup options → Restart now → Troubleshoot → Advanced options → Startup settings → Restart → F5.

Note: Windows 8 reached end-of-life in January 2023 - running on it puts you at much higher risk of reinfection.

Windows 7

Click Start → Shut Down → Restart → OK. As the system boots, press F8 repeatedly until the Windows Advanced Options menu appears, then choose Safe Mode with Networking.

Note: Windows 7 reached end-of-life in January 2020 - running on it puts you at much higher risk of reinfection.

Phase 2~ 15 min

Identify - find what's hiding

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3

Inspect running processes with Process Explorer

Tool: Process Explorer5 min

Download Process Explorer from Microsoft Sysinternals. Run it as Administrator. Click Options → Verify Image Signatures and View → Lower Pane View → DLLs.

Sort by "Verified Signer." Anything unsigned running from %AppData%, %LocalAppData%, %Temp%, or %ProgramData% is suspicious. Right-click → Properties to see the full image path. Right-click → "Search Online" to look up unfamiliar process names.

Why not just Task Manager

Task Manager hides full file paths, doesn't show digital signatures, and groups processes in ways that make malware easy to miss. Process Explorer is the same tool Microsoft engineers use.

4

Map every persistence point with Autoruns

Tool: Autoruns 14.x10 min

Download Autoruns. Right-click Autoruns.exe and choose Run as administrator - without elevation, Autoruns can't inspect protected registry hives.

In the menu, open Options → Hide Microsoft Entries and Options → Hide Empty Locations, then click Refresh.

Modern trojans don't just live in startup. Walk through these tabs and look for unsigned or unfamiliar entries:

• Logon - classic Run/RunOnce keys
• Scheduled Tasks - frequent hiding spot, especially tasks with PowerShell, MSHTA, or rundll32 actions
• Services - unsigned services in non-Microsoft folders
• WMI - Event Subscriptions are a stealthy persistence mechanism (MITRE T1546.003)
• Image Hijacks - Image File Execution Options "Debugger" abuse
• AppInit - DLLs loaded into every GUI process
• Browser plug-ins - unsigned add-ons across all installed browsers

Pro tip

Right-click any suspicious entry → "Jump to Image" to see the actual file. Right-click → "Search Online" opens VirusTotal for the file hash. Don't delete yet - just write down the file paths and entry names. We'll remove them after the scans.

5

Check the hosts file and DNS settings

3 minBuilt into Windows

Trojans often redirect bank, antivirus, and update domains to attacker-controlled servers by editing the hosts file or DNS settings.

Hosts file: Open Notepad as Administrator and open C:\Windows\System32\drivers\etc\hosts. Legitimate entries are commented with #. Any uncommented IP-to-domain mapping is suspicious - especially redirects for microsoft.com, windowsupdate, or your bank.

DNS settings: Open Command Prompt as Administrator and run ipconfig /all. Confirm your DNS servers point to your ISP, your router, or a known public resolver (Cloudflare 1.1.1.1, Google 8.8.8.8). Then open Settings → Network & internet → [your adapter] → DNS server assignment and verify both DNS and DNS over HTTPS (DoH) settings haven't been hijacked.

Why this matters

A clean PC with hijacked DNS is still a compromised PC. You'll think you're at chase.com and you'll be at the attacker's clone.

Phase 3~ 60-90 min

Remove - three scans, one cleanup

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No single antivirus catches everything. The order below is intentional: offline scan first (catches rootkits before Windows fully loads), then on-demand scanners on the running system, then manual cleanup of anything they missed.

6

Run Microsoft Defender Offline

Tool: Built into Windows15 min

Reboot to normal Windows. Open Windows Security → Virus & threat protection → Scan options. Select Microsoft Defender Antivirus (offline scan) and click Scan now. Your computer will restart into a stripped-down environment and scan before the full operating system loads.

Why this comes first

Rootkits and bootkits hide from any scanner running on the same Windows session that's already infected. A pre-boot offline scan sees the disk before the malware can hide itself.

Recommended antivirus

Combo Cleaner

VB100 certified. Includes anti-trojan, registry/persistence scanning, anti-spyware in one pass. The 7-day free trial is available.

Download Combo Cleaner

7

Run Combo Cleaner full system scan

Tool: Combo Cleaner20-40 min

Install Combo Cleaner and run a full system scan (not the quick scan). Let it complete fully, review the detected threats, and apply the recommended actions. Combo Cleaner will quarantine known trojans and registry persistence.

8

Run Microsoft Safety Scanner as a second-opinion scan

Tool: Microsoft Safety Scanner15 min

Download Microsoft Safety Scanner (MSERT.exe), Microsoft's free on-demand tool. The binary expires every 10 days, which means every download has the latest signatures. Run a full scan after Combo Cleaner to catch anything one engine alone might miss.

Why a second scan

Different scanning engines catch different threats. Running an additional Microsoft scan after Combo Cleaner is the single most underused verification step in malware removal.

9

Manually remove anything still listed in Autoruns

Tool: Autoruns10 min

Reopen Autoruns. Anything you flagged in Step 4 that's still present hasn't been caught by the automated scans. For each remaining suspicious entry: right-click → Delete in Autoruns (this removes the persistence registration), then navigate to the file path and delete the actual file. Empty the Recycle Bin.

Important

Some malware files reappear after deletion because something else on the system recreates them. If you delete a file and it returns within minutes, you have a remaining persistence point that Autoruns didn't show - usually a service or scheduled task running under SYSTEM. Re-run the scans from Steps 6-8 or proceed to a clean install (see end of guide).

Phase 4~ 15 min

Recover - restore browsers and security

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10

Reset browsers and clear notification permissions

5 min

Trojans and adware frequently hijack browsers - change the default search engine, install rogue extensions, or grant themselves notification permissions to keep displaying scam pop-ups even after the malware is gone.

• Chrome: visit chrome://settings/reset and click "Restore settings to their original defaults." Then visit chrome://settings/content/notifications and remove any unfamiliar sites.
• Edge: visit edge://settings/reset. Then check edge://settings/content/notifications.
• Firefox: open about:support and click Refresh Firefox (Firefox uses "Refresh," not "Reset"). Then check Settings → Privacy & Security → Permissions → Notifications.

Review installed extensions in each browser and remove anything you don't recognize, especially extensions you didn't install yourself.

11

Re-enable Defender, Tamper Protection, and update everything

10 min

Many trojans disable security software. Open Windows Security → Virus & threat protection → Manage settings and confirm Real-time protection, Cloud-delivered protection, and Tamper Protection are all turned on. Tamper Protection prevents malware from disabling Defender silently.

Then run Windows Update (Settings → Windows Update → Check for updates) and update your browsers and applications. The infection vector that let the trojan in originally usually involves outdated software.

Phase 5~ 15 min + 7 days

Verify & secure

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12

Change passwords from a clean device

20 min⚠ Critical

If the trojan was an info-stealer (Lumma, RedLine, Vidar, and similar are extremely common), assume every password saved in your browser is compromised. Change them from a different, known-clean device - your phone is fine if it's not infected.

Recommended order:

1. Primary email first - it's the recovery hub for everything else
2. Banking and financial accounts
3. Password manager master password (if you use one)
4. Social media, shopping, and remaining accounts

Where available, enable phishing-resistant multi-factor authentication (passkeys / FIDO2 hardware keys / authenticator apps) - SMS-based MFA is bypassable by sophisticated attackers.

13

Verify the clean and monitor for 7 days

5 min + 1 week monitoring

Reconnect to the network and run one final full scan with Combo Cleaner. Open Task Manager (Ctrl + Shift + Esc) and switch to the Startup apps tab - confirm nothing suspicious has reappeared.

Over the next 7 days, watch for symptom recurrence: unexpected high CPU usage, unknown processes returning, browser redirects, or pop-ups. If anything returns, you missed a persistence point and the procedure needs to be repeated - or you may have a deeper compromise that requires a clean install.

When to clean install Windows instead

Manual removal isn't always the right answer. Reinstalling Windows from scratch is the only way to be 100% certain when:

• The malware reappears after every removal attempt
• A bootkit or UEFI rootkit was detected (this class of threat sits below the operating system and survives a normal Windows reinstall)
• A confirmed credential-theft trojan ran with administrator privileges (Lumma, RedLine, Vidar) - the system likely has multiple unknown payloads
• The PC is used for online banking, business email, or anything where partial doubt isn't acceptable

A clean install is a 30-60 minute process: Windows 11 reinstall via Settings → System → Recovery → Reset this PC → Remove everything → Cloud download. Back up documents to external storage first, scan the backup with Combo Cleaner before restoring it, and reinstall applications fresh - never restore them from a backup of the infected system.

Important: Manual removal requires advanced computer skills. If you're not confident identifying system files from malicious files, run an automated scan with Combo Cleaner and Windows Defender and stop there - that path catches the vast majority of consumer trojans without the risk of breaking Windows by deleting the wrong file.

Frequently Asked Questions (FAQ)

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

No, BitRAT can be removed by following the steps provided in our removal guide above. It is not necessary to format the storage device to eliminate this malware from the operating system.

What are the biggest issues that malware can cause?

Malware can be used to encrypt files, steal identities, steal money, hijack personal accounts, mine cryptocurrency, inject additional malware, etc. It depends on the type of malware.

What is the purpose BitRAT?

This RAT can record video and audio using a webcam and microphone, manage the files stored in the system, download and upload files (and execute downloaded files), extract login credentials stored in browsers and other apps, and log keystrokes. Also, it can mine cryptocurrency.

How did this malware infiltrate my computer?

It is known that cybercrimnials distribute BitRAT via emails - they send emails containing malicious attachments (Microsoft documents). In other cases, malware is distributed via various untrustworthy sources for downloading software, cracked/pirated software distribution pages, fake updaters, etc.

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner can detect almost all known malware and remove it from the compromised device. If a computer is infected with high-end malware, it has to be scanned using a full system scan. Malware of this kind can hide deep in the operating system. Thus, running a quick scan is not enough to detect and remove such malware.