How to eliminate DUCKTAIL malware from the operating system

What is DUCKTAIL?

DUCKTAIL is the name of a malicious program designed to steal Facebook Business accounts. The observed attacks have been highly targeted.

Research by WithSecure Intelligence suggests that this malware has been around since 2021 and is associated with Vietnamese cyber criminals. At the time of writing, DUCKTAIL continues to receive updates, including new abilities to evade Facebook's security measures.

DUCKTAIL malware overview

At the time of writing, DUCKTAIL's campaigns have been highly individualized. The cyber criminals behind this malware search Facebook's Business/Ads platform for targets of interest and go after high-ranking individuals.

The goal is to gain access to accounts of victims who have significant or total control over a Facebook business page. For example, DUCKTAIL's ideal victims would have either Admin access or a Finance editor role. The former allows full control over the business account like deletion and management (e.g., settings, privileges, roles, tools, etc.). While hijacking the latter would enable the cyber criminals to view financial data (e.g., transactions, invoices, spending, payment methods, credit cards, etc.) and abuse it.

Following successful infiltration, DUCKTAIL begins its operation by checking for installed browsers, specifically looking for Google Chrome, Mozilla Firefox, Microsoft Edge, or Brave. From that point, the malware seeks to identify cookie paths and extract those relating to Facebook sessions.

These cookies can contain data necessary for the malware to gain access to the victim's Facebook account, but the malicious program gathers any relevant information it can find - including any and all security credentials.

DUCKTAIL also checks whether 2FA (two-factor authentication) is required - if it is - the program tries to acquire the recovery codes. In addition to session cookies, the malware can extract access tokens, user agents, IP addresses (geolocations), 2FA codes, and so on.

DUCKTAIL usually steals the Business accounts through associated personal Facebook accounts. Information such as victims' user ID, name, birthday, and email - is of interest to this program. The malware adds the emails in possession of the cyber criminals to Facebook Business accounts - thus establishing control over them.

Once an associated business/ad account is breached, DUCKTAIL collects the following data: name(s), verification status(es), connected account number, ad spending and payment cycles, ad account permissions, set currency, pending users, owners, member roles, linked emails, client data, and so forth.

To summarize, DUCKTAIL infections can result in severe privacy issues, significant financial losses, and identity theft. If you suspect that your device is infected with DUCKTAIL (or other malware), we strongly advise using an anti-virus to remove it immediately.

And if you believe that your account(s) have been compromised - change the passwords and contact Facebook's official support without delay.

To ensure the safety of your accounts, we recommend choosing two-factor/multi-factor authentication when possible, using strong passwords, and selecting prudent access/privilege/privacy settings.

Information-stealing malware examples

We have analyzed thousands of malicious programs, including those that steal particular information like - YTStealer - that targets YouTube accounts, and FFDroider, DevilsTongue, Redox, Ducky - which aim to steal Facebook accounts amongst other data.

This type of malware can seek a wide variety of information, and these malicious programs can have different/additional functionalities. However, regardless of how malware operates - system infections endanger device and user safety. Hence, it is essential to eliminate all threats immediately upon detection.

How did DUCKTAIL infiltrate my computer?

As previously mentioned, DUCKTAIL infection chains are tailor-made for the potential victims. WithSecure Intelligence has noted instances where this malware was delivered via the LinkedIn business networking platform.

WithSecure Intelligence researchers have also observed the infectious files starting DUCKTAIL's infection chains being hosted on cloud services such as Dropbox, MediaFire, and iCloud. The files themselves were usually archives with (often generic) names relating to the targeted business.

Generally, malware is spread using phishing and social engineering techniques. Virulent files can be in various formats, e.g., archives (ZIP, RAR, etc.), executables (.exe, .run, etc.), Microsoft Office and PDF documents, JavaScript, and so on. When an infectious file is executed, run, or otherwise opened - the malware download/installation process is initiated.

The most commonly used malicious software distribution methods include: drive-by (stealthy/deceptive) downloads, attachments/links in spam mail, online scams, untrustworthy download sources (e.g., freeware and third-party websites, P2P sharing networks, etc.), malvertising, illegal program activation tools ("cracks"), and fake updates.

How to avoid installation of malware?

We advise against opening the attachments and links found in suspicious/irrelevant emails and messages since that can lead to a system infection. It is just as important to exercise caution when browsing - as fraudulent and malicious material usually looks legitimate.

We also recommend downloading from official and verified channels. Additionally, all programs must be activated and updated with tools provided by genuine developers, as illegal activation ("cracking") tools and fake updaters may contain malware.

We must emphasize the importance of having a reputable anti-virus installed and kept up-to-date. This software 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 Windows to automatically eliminate infiltrated malware.

Update 5 May, 2023 - Cyber criminals are currently spreading DUCKTAIL malware via malicious shortcut (.LNK) files and disguising them as PDF or other similar documents. These shortcuts are distributed using email spam campaigns. The malicious shortcut usually comes with an icon of PDF document in order to trick users into execution. Once opened, the shortcut stealthily downloads malware alongside with a random PDF document as a disguise.

Example of a malicious shortcut and its target:

Screenshot of the disguise PDF document downloaded by this shortcut:

Update November 9, 2023 – new campaigns spreading DUCKTAIL have been observed. These attacks aim to carry out identity theft. The operations rely on compromised LinkedIn accounts to send job offer messages to users. The campaigns heavily target Italian companies, particularly technology-oriented ones.

One of the known operations sought financial sector employees of said companies. In this scheme, the victim is contacted via LinkedIn regarding a job offer. Several messages later, they are sent a PDF file detailing the open position of Senior Manager at the EA (Electronic Arts) video game company.

Two links can be found in the document, one leading to a page imitating EA's official website. This is a phishing site presenting a candidate registration form that requires logging in.

The other link leads to the download of a ZIP archive (titled "Senior_Manager_EA_Sport.zip"; may vary) from the Microsoft OneDrive file hosting service. The archive contains three MP4 format video files and two executables bearing the Microsoft Word logo as their icon.

The executables are designed to initiate DUCKTAIL's infection chain. It is noteworthy that once launched, the malicious executables display a decoy PDF document relating to the job offer.

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

No, DUCKTAIL's removal does not necessitate such drastic measures.

What are the biggest issues that DUCKTAIL malware can cause?

DUCKTAIL specifically targets Facebook Business accounts. Therefore, the threats these infections pose include: compromise of various Facebook accounts (personal, business, ad, etc.), severe privacy issues, significant financial losses, and identity theft.

What is the purpose of DUCKTAIL malware?

Most malicious programs are used to generate revenue, and DUCKTAIL is not an exception. However, it is worth mentioning that malware can be released for testing purposes or to cause pointless mayhem for the attackers' amusement. Malware attacks can also be motivated by personal grudges and political/geopolitical reasons.

My accounts have been stolen, what should I do?

Firstly, change the passwords of all potentially compromised accounts without delay. Secondly, inform their official support. If you suspect that your personally identifiable, financial, or other vulnerable information has been exposed - immediately contact the corresponding authorities.

How did DUCKTAIL malware infiltrate my computer?

The most popular malware distribution methods include: drive-by downloads, spam emails and messages, dubious download channels (e.g., unofficial and free file-hosting websites, P2P sharing networks, etc.), online scams, illegal software activation ("cracking") tools, fake updates, and malvertising. Some malicious programs are also capable of self-spreading via local networks and removable storage devices (e.g., external hard drives, USB flash drives, etc.).

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner is designed to detect and remove threats. It can eliminate most of the known malware infections. However, it must be stressed that performing a complete system scan is paramount - since sophisticated malicious software tends to hide deep within systems.