How to remove Trojan Win32/Tiggre!rfn malware

What kind of malware is Trojan Win32/Tiggre!rfn?

Trojan Win32/Tiggre!rfn is high-risk malware designed to perform a number of malicious tasks on victims' computers. It is also known as "Trojan.GenericKD.12694003" (by BitDefender) and "W32/Autoit.CGO!tr" (by Fortinet).

Trojan Win32/Tiggre!rfn is distributed in various ways, including spam emails (malicious attachments), fake Adobe Flash Player updaters, malicious websites, chain infections, and even Facebook messages.

Trojan Win32/Tiggre!rfn malware in detail

Trojan Win32/Tiggre!rfn is versatile malware, since it performs various functions depending on developers' choices. For example, it can misuse system resources to mine cryptocurrency. The entire crypto-mining process essentially based on solving various "mathematical equations". Mining tools employ system resources to perform calculations.

Each time an "equation" is solved, a single unit of currency (e.g., 1 Bitcoin) is mined. Since an identical "equation" is solved by a number of computers simultaneously, the reward is split between each device depending on the power of the device and how much work is performed. All revenue is received by cyber criminals (crypto wallet), whilst users receive nothing in return.

In fact, all this is done without their consent, and since mining takes up to 100% of computer resources, systems often become unstable and virtually unusable. Furthermore, within certain circumstances (high room temperatures, poor cooling systems, etc.) hardware can be damaged (components might overheat).

Trojan Win32/Tiggre!rfn also gathers various data, including saved logins/passwords, keystrokes, banking information, and so on.

Collected data is often misused to generate revenue. Therefore, the presence of malware such as Trojan Win32/Tiggre!rfn might lead to serious financial and privacy issues (e.g., cyber criminals can transfer funds to their accounts, purchase illegal items under your name, and so on).

In some cases, Trojan Win32/Tiggre!rfn infiltrates systems along with a number of adware-type applications. These programs are not as harmful as Trojan Win32/Tiggre!rfn, but can be frustrating and problematic. Adware-type programs typically deliver intrusive advertisements and gather sensitive data.

Intrusive ads conceal underlying website content (thereby significantly diminishing the browsing experience), and also redirect to malicious sites and even run scripts that stealthily download and install malware. Clicking these ads can lead to malicious sites.

Furthermore, adware gathers IP addresses, URLs visited, search queries, pages viewed, and other data relating to browsing activity. Collected information is shared with third parties (potentially, cyber criminals). Therefore, adware poses a threat to your privacy and Internet browsing safety. For these reasons, all adware-type apps must be eliminated immediately.

Similarities with other malware

Trojan Win32/Tiggre!rfn is very similar to Pony, TrickBot, and FormBook. In fact, there are dozens of viruses that also gather information, mine cryptocurrencies, and perform other malicious tasks. Adware-type apps share many similarities.

By offering 'useful features', unwanted programs attempt to give the impression of legitimacy, however, rather than enabling the functions promised, adware poses a direct threat to your privacy and Internet browsing safety. The only purpose of this software is to help developers generate passive revenue.

How did Trojan Win32/Tiggre!rfn infect my computer?

As mentioned above, Trojan Win32/Tiggre!rfn is promoted using spam emails, fake Flash Player updaters, and Facebook. Spam emails contain malicious attachments (e.g., MS Office documents, JavaScript files, etc.) that, once opened, stealthily download and install malware. Fake updaters claim that the player is outdated (although it is not) and encourage users to renew it.

Rather than updating the player, however, these tools download and install Trojan Win32/Tiggre!rfn. Criminals also proliferate this malware via malicious sites that, once opened, execute scripts designed to download and install Trojan Win32/Tiggre!rfn without consent.

Another method is "chain-infecting": a computer is infected with malware that proliferates other viruses (in this case, Trojan Win32/Tiggre!rfn). Developers also use scripts that send spam messages on Facebook. The message simply contains a video file, however, this is a disguise - rather than opening the video, the user will open a AutoIt script that will infect the system.

How to avoid installation of malware?

The main reasons for computer infections are poor knowledge and careless behavior. The key to safety is caution. Therefore, pay close attention when browsing the Internet. Think twice before opening files/links received via email, Facebook accounts, Skype, and so on.

If files/links seem irrelevant or have been sent from suspicious/unrecognizable names/email addresses, delete these messages immediately and certainly do not open attached files/links. Furthermore, keep installed applications up-to-date and remember that criminals proliferate malware via fake updaters.

Therefore, apps should be renewed using implemented update features or tools provided by the official developers only. Having a reputable anti-virus/anti-spyware suite installed and running is also paramount.

If you believe that your computer is infected with Trojan Win32/Tiggre!rfn, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

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 Trojan Win32/Tiggre!rfn malware, should I format my storage device to get rid of it?

You can remove Trojan Win32/Tiggre!rfn from the operating system by following the steps provided in our removal guide. It is not necessary to format the storage device to remove it.

What are the biggest issues that malware can cause?

The biggest issues that software of this type can cause are monetary and data loss, identity theft, decreased computer performance, and further infections.

What is the purpose of Trojan Win32/Tiggre!rfn malware?

It can be used for different purposes. It is known that cybercriminals use it to mine cryptocurrency and (or) gather various data (including saved logins/passwords, keystrokes, and banking information). We also found that this malware often injects some adware.

How did Trojan Win32/Tiggre!rfn infiltrate my computer?

The Trojan Win32/Tiggre!rfn malware is distributed via spam emails (malicious attachments), fake Adobe Flash Player updaters, malicious web poages, other malicious programs, and even Facebook messages.

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner will remove malware from the operating system. It can detect almost all known malware. If a computer is infected with high-end malware, it must be scanned using a full scan. Otherwise, the antivirus program will not detect malware that hides deep in the operating system.