How to protect computers from attack by the Forbix worm

What kind of malware is Forbix?

Forbix is a malicious program and classified as a 'worm'. It can infect available drives, protect itself against removal, update itself, perform a second stage payload, and communicate through a C2 server. Generally, worms are malicious programs that can replicate to spread to other computers.

They can be used to perform ransomware attacks, steal personal details such as passwords, or add infected computers to botnets. In summary, worms can be used for a number of malicious purposes.

More about Forbix

If a worm is used to install a 'backdoor', it can allow cyber criminals to control a computer remotely (add it to a botnet), and use it to send spam or perform DoS attacks. The victim's computer could be used to send spam emails designed to trick other people into installing malicious software, visiting untrustworthy websites, and so on.

'DoS attacks' are effectively cyber attacks designed to make machines or networks inaccessible for a specific period of time. To perform these attacks, cyber criminals use infected computers that are added to a botnet. For example, other computers could be used to connect to a particular website to overload it and prevent access by other users.

Furthermore, worms can be used to proliferate malicious software such as ransomware. These programs encrypt files stored on computers and force victims to pay ransoms. Typically, people who have computers infected with ransomware experience data loss. This can also lead to monetary loss.

As we mentioned, Forbix can infect connected drives such as USBs. Therefore, it can spread to other computers when users insert/connect an infected drive. It can also update itself to a newer (potentially, more harmful) version. Forbix is difficult to remove - one of its capabilities is to protect itself from removal.

This worm can also be used to infect computers with cryptocurrency miners. These programs use victims' computer hardware to mine cryptocurrency. Generally, these processes cause high GPU and/or CPU usage, which results in higher electricity consumption and bills.

Cyber criminals who proliferate programs of this type seek to generate revenue at the victim's expense. Remove Forbix from your computer immediately.

Worms like Forbix in general

Another example of a 'worm'-type program is Retadup. Typically, worms spread on other computers. Their purpose is to infect as many systems as possible.

They are often used to infect computers with additional malware such as ransomware, malicious cryptocurrency miners, password stealers, and so on. Their payload can vary, however, installed worms mostly cause serious damage including data and financial loss.

How did Forbix infiltrate my computer?

Typically, cyber criminals proliferate malicious programs through spam campaigns, Trojans, untrustworthy software of file download channels, unofficial activation/'cracking' tools and fake software updating tools. Spam campaigns are used to proliferate malware through files attached to emails.

Cyber criminals send these emails to many people. Once opened, the attached files install a malicious program. Some examples of files that cyber criminals attach to such emails are MS Office or PDF documents, archive files such as ZIP, RAR, JavaScript files, executables such as .exe, etc.

Trojans are malicious programs that cause chain infections. To proliferate malware, however, a Trojan must already be installed on the system.

After installation, it starts installation of other malicious programs. Untrustworthy software download sources such as freeware download websites, free file hosting pages, various Peer-to-Peer networks such as eMule, torrents, and other similar sources can be used to proliferate malicious files/programs.

To spread malware through these, cyber criminals disguise malicious files as legitimate and harmless. If downloaded and opened, however, they infect computers with high-risk malware.

Unofficial software activation tools supposedly allow users to bypass paid activation of licensed software, however, people who use them often infect their computers with malicious programs (these tools distribute malware).

Fake software update tools usually infect systems by exploiting bugs/flaws of outdated software or by downloading, installing computer infections rather than updates, fixes, and so on.

How to avoid installation of malware

Irrelevant emails that contain attachments or web links and are received from unknown/suspicious addresses should not be trusted. Typically, cyber criminals disguise them as official, however, it is not safe to open these attachments or click the links.

Do not download or install software using third party downloaders/installers, or use any other dubious sources to download files or programs. The best way to achieve this is via official websites and direct download links. All installed software should be updated through tools or implemented functions provided by official software developers.

Do not use unofficial tools that supposedly activate licensed software. This is illegal and using 'cracking' tools often infects computers with unwanted, malicious software.

To avoid damage caused by malware, regularly scan systems with reputable anti-virus or anti-spyware software. Additionally, it is important to keep such software up-to-date. 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.

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)

What are the biggest issues that malware can cause?

Malware can be used to steal identities, personal accounts, money, inject additional malware, add computers to botnets, launch DDoS attacks, mine cryptocurrency, and more.

What is the purpose of Forbix malware?

Forbix is a worm - a type of malware that can inject other malware and perform other malicious activities. It may be used to infect computers with ransomware, cryptocurrency miners, Trojans, and other malicious software. More information about worms is provided in our article above.

How did a malware infiltrate my computer?

Worms can self-spread through removable storage devices (e.g., external hard drives, USB flash drives, and similar). Also, threat actors use phishing and other social engineering techniques (e.g., deceptive emails, fake system warning messages, etc.), drive-by downloads, P2P networks, unofficial websites, and similar ways to distribute malware.

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner will scan the operating system and remove malware. It can detect almost all known malware infections. Computers infected with high-end malware must be scanned fully (using a full scan option). Otherwise, antivirus solutions will not detect malware that hides deep in the system.