How to remove QuimaRAT malware from the operating system

What kind of malware is QuimaRAT?

QuimaRAT is a Java-based Remote Access Trojan (RAT) sold to cybercriminals as a subscription service. This model, known as Malware-as-a-Service (MaaS), allows anyone who pays the fee to deploy the RAT against targets of their choosing.

According to research published by LevelBlue's SpiderLabs team, QuimaRAT targets Windows, macOS, and Linux. It gives operators full remote control over infected devices and can steal passwords, record keystrokes, and access the victim's webcam and microphone.

The malware is marketed as "QuimaRAT v2.0" on dark web forums. On Windows, it runs fully hidden with no visible windows, no system tray icon, and no trace of its activity for the victim to notice.

QuimaRAT overview

QuimaRAT is built around a modular architecture that allows operators to extend its capabilities through encrypted plugins. It connects to the attacker's command-and-control server via TCP, WebSocket, TLS, or HTTPS, with a watchdog component keeping the connection alive.

The full suite includes four components: Quima Control (the RAT itself), Quima Builder, Quima Loader, and Quima Dropper. The Loader stages payloads through the browser cache, blending in with files the operating system already trusts to avoid detection by security software.

The RAT is written in Java and built using Apache Maven, with operator settings stored in an encrypted configuration file. At startup it checks for sandbox or virtual machine environments and can alter its behavior accordingly, making automated analysis more difficult.

QuimaRAT's capabilities

QuimaRAT ships with over 70 modules for Windows and 44 for macOS and Linux. Core remote-control features include remote desktop access, HVNC (a hidden screen-control channel), webcam and microphone capture, real-time keylogging, and screenshot taking.

A built-in credential-theft module recovers passwords and tokens across more than 14 categories. This covers saved login data from Chrome, Firefox, and similar browsers, along with Discord, Steam, and various cryptocurrency wallets and wallet browser extensions.

Operators can also browse and manage files on the infected system, run commands via a remote shell, view or kill processes, and route traffic through reverse proxy and port-forwarding features.

The malware additionally supports DLL injection and can download and execute additional payloads on demand. It includes a built-in crypto clipper that monitors the clipboard and silently replaces copied cryptocurrency wallet addresses with those belonging to the attacker.

Persistence and defense evasion

QuimaRAT establishes persistence differently on each supported platform. On Windows it writes to Windows Registry Run keys, creates scheduled tasks, and adds entries to startup folders. On Linux it uses crontab reboot tasks and desktop autostart entries. On macOS it installs LaunchAgent plist files.

To hinder detection and removal, the malware can disable Windows Defender and the firewall, and bypass User Account Control. It applies ProGuard obfuscation and AES-256 string encryption to slow down reverse engineering. Operators can also enable a Pastebin-based option for rotating C2 server addresses.

The Quima Builder packages the implant in twelve output formats, including JAR, EXE, APP, SH, BAT, VBS, and native binaries. The same core RAT can therefore be deployed across all three supported platforms with no code changes needed.

QuimaRAT pricing

QuimaRAT is sold on a tiered subscription model. Prices are $150 per month, $300 for three months, $500 for six months, $700 for twelve months, or $1,200 for a lifetime license. It is advertised on dark web cybercriminal forums alongside similar MaaS tools.

Conclusion

QuimaRAT gives cybercriminals a broad toolkit for remote control, credential theft, clipboard hijacking, and further malware deployment. Its stealth design and anti-detection features mean most victims have no indication the malware is running. If QuimaRAT is on your system, it should be removed immediately.

More examples of RATs are msaRAT, Dolphin X, and Starland.

How did QuimaRAT infiltrate my computer?

LevelBlue SpiderLabs researchers Chen Aviani and Nikita Kazymirskyi documented that QuimaRAT is sold on dark web forums as a subscription service. Operators purchase access and use the Quima Builder to produce their own payloads, then distribute them through whatever methods they choose.

No specific active campaigns have been publicly identified at the time of writing, so the delivery method in any given incident depends on the individual operator. Common options include phishing emails with malicious attachments, fake software download pages, and pirated or cracked software bundles.

Malware of this kind also spreads through malvertising, unofficial download sites, and social engineering. Because the builder supports twelve output formats (including EXE, JAR, VBS, and SH), QuimaRAT payloads can be packaged to resemble almost any type of file.

How to avoid installation of malware?

Download software only from official developer websites and verified app stores. Ignore unsolicited emails with attachments or links from unknown senders. Never use pirated software, key generators, or software cracks, as these regularly serve as a vehicle for hidden malware.

Keep your operating system and all installed applications updated, and run reputable antivirus or anti-malware software. Be cautious with browser notifications from unfamiliar websites. 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.

QuimaRAT promotional listing on hacker forums (source: levelblue.com):

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 QuimaRAT malware, should I format my storage device to get rid of it?

Formatting will remove QuimaRAT, but it will also erase every file on the drive. A reputable security tool such as Combo Cleaner should be tried first, as it can eliminate the malware without destroying your data.

What are the biggest issues that QuimaRAT malware can cause?

QuimaRAT can let attackers take full remote control of an infected device, steal passwords and session tokens, hijack cryptocurrency transactions via clipboard replacement, and deploy additional malware. Consequences include identity theft, financial fraud, and loss of access to accounts.

What is the purpose of QuimaRAT malware?

QuimaRAT is designed to give its operators remote control over infected computers. It also steals credentials and tokens, redirects cryptocurrency clipboard entries to the attacker's wallet, and can serve as a platform for delivering further malware to the victim's system.

How did QuimaRAT malware infiltrate my computer?

QuimaRAT is sold through dark web forums as a subscription service, so the delivery method depends on the operator who purchases it. Common vectors include phishing emails, fake software download pages, and cracked or pirated software packages containing hidden payloads.

Will Combo Cleaner protect me from malware?

Yes. Combo Cleaner can detect and remove most known malware, including threats like QuimaRAT. Because RATs can embed themselves across multiple system locations, running a full system scan is the best way to ensure no components remain on your device.