How to remove the Smoke Loader malware from your operating system

What kind of malware is Smoke Loader?

Smoke Loader is trojan-type malware used to proliferate various other viruses. Cyber criminals proliferate Smoke Loader using spam emails (malicious attachments).

Therefore, it typically infiltrates systems without users' consent. After successful infiltration, the malware performs a number of actions, such as: 1) self-updating; 2) removing all traces, and; 3) downloading other viruses.

Smoke Loader malware overview

Immediately after infiltration, Smoke Loader connects to a remote Command and Control (C&C) server to download its latest version. In addition, it modifies the creation/modification date of its executable. In doing so, Smoke Loader makes it impossible to detect this malware by checking the list of recently-modified files.

Access to this executable is also blocked, since Smoke Loader removes read/write permissions. To "disguise" its connection to the C&C server, Smoke Loader continually sends requests to legitimate URLs. The traffic is moderately encrypted. Judging on this behavior, Smoke Loader can be classed as an advanced trojan.

Smoke Loader is uses to spread a variety of other viruses (for example, XMR Miner). The behavior of the promoted malware may vary - viruses often mine cryptocurrencies, gather sensitive information, use victims' computers to send spam, etc.

• Cryptomining software employs system resources to mine cryptocurrencies (e.g., Bitcoins, Monero, etc.) The process takes up to 100% of hardware resources. Therefore, the system becomes unstable and virtually unusable - it can easily crash, which might lead to permanent data loss.
• Furthermore, hardware running at its fullest capacity generates excessive heat. Within certain circumstances (high room temperatures, bad cooling systems, and so on), mining cryptocurrency can damage the hardware (it can simply overheat). Note that users receive nothing in return - all revenue goes to the cyber criminals.
• High risk data-tracking malware typically records extremely sensitive information. The list of collected data types often includes (but it is not limited to) keystrokes, saved logins/passwords, banking information, websites visited, and even saved files.
• Therefore, these viruses pose a significant threat to users' privacy - collected data can be used to steal their identities to perform money transfers, online purchases, etc. The presence of these viruses can lead to serious privacy issues and significant financial losses.
• The infiltrated malware might also spread itself by using victims' identities. The viruses simply hijack web browsers (to use social networks) and other communication software (e.g., Skype) to send malicious files/URLs (spam) to all of the contacts. These files/URLs are typically disguised (for example, the malware sends them with messages such as "Check my new photo").
• The disguise is often obvious, so these bogus messages should be easy to spot. If you have received these messages/files from your 'friends', think twice before downloading and opening them. If a message seems suspicious (especially if it is not in your native language), do not open it.

In summary, the presence of Smoke Loader trojan can lead to a number of issues and, therefore, must be eliminated immediately. If you have noticed that your computer is running slowly or there is suspicious activity (someone using your accounts, you encounter questionable files/executables, etc.), immediately scan the system with a legitimate anti-virus/anti-spyware suite.

Examples of malware with similar functionalities

There are a number of viruses that perform the aforementioned actions including, for example, JSMiner-C, COINMINER, Adwind, Emotet, and LokiBot.

They are developed by different cyber criminals and their behavior might also differ. They do, however, have one thing in common: all are used to generate revenue for the developers. Therefore, the presence of these viruses is extremely dangerous.

How did Smoke Loader infect my computer?

As mentioned above, Smoke Loader is distributed using spam emails. These are delivered with various MS Office documents (Word, Excel, etc.) falsely presented as job applications and other work-related documents. Once the attachment is opened, users are immediately asked to activate macros to display the content properly.

Once a macro is executed, however, the script connects to a remote IP address and infiltrates Smoke Loader into the system. Spam emails are not the only way to proliferate malware - criminals are also likely to use intrusive advertisements, fake updaters, and a deceptive marketing method called "bundling" (stealth installation of rogue programs with regular software).

How to avoid installation of malware?

To prevent this situation, be very cautious when browsing the Internet and especially when downloading/installing software. Carefully analyze each email attachment. If the file seems irrelevant or has been received from a suspicious/unrecognizable email address, do not open it and delete the email immediately.

Note that intrusive ads typically seem legitimate, since developers invest many resources into their design. Once clicked, however, they redirect to dubious websites (gambling, adult dating, pornography, and similar). These ads are often delivered by adware-type PUPs.

Therefore, if you encounter dubious redirects, immediately remove all suspicious apps and browser plug-ins. We also strongly recommend that you carefully analyze each window of the download/installation processes and opt-out of all additionally-included programs.

You are advised to download your programs from official sources only, using direct download links. Third party downloaders/installers often include rogue apps, and thus should never be used. The same applies to software updates.

Installed programs must be kept up-to-date, however, this should be achieved only through implemented functions or tools provided by the official developer. Having a reputable anti-virus/anti-spyware suite installed and running is also paramount. The main reasons for computer infections are poor knowledge and careless behavior - the key to safety is caution.

If your computer is already infected with PUPs, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate them. If your computer is already infected with Smoke Loader, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.

Malicious MS Excel attachment asking to activate macros:

Update June 8, 2020 – Smoke Loader trojan has been recently observed spreading Avaddon ransomware, as well as njRat malware.

Update February 5, 2025 – new Smoke Loader campaign has emerged. This trojan was observed being proliferated via targeted spam campaigns that leveraged a vulnerability in the 7-Zip file archiver tracked as CVE-2025-0411 (currently patched through the 7-Zip version 24.09).

This campaign was facilitated by Russian threat actors with clear geopolitical motivations, with the likely goal being cyber espionage. The spam emails were sent to Ukrainian governmental bodies and businesses.

Some of the known targets include: Zalishchyky City Council, Verkhovyna District State Administration (Ivano-Frankivsk oblast administration), Kyivpastrans (public transportation service in Kyiv), Kyivvodokanal (water supply company in Kyiv), Dnipro City Regional Pharmacy, SEA Company (manufacturer of applications and electronics), and VUSA (insurance company).

The cyber criminals have also used stolen governmental accounts to send the malspam. To elaborate, emails were sent from an account belonging to the State Executive Service of Ukraine (now merged with the Ukrainian Ministry of Justice). More information on this campaign can be found in an article by Peter Girnus on the Trend Micro website.

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

Malware removal rarely necessitates formatting.

What are the biggest issues that Smoke Loader malware can cause?

The threats posed by an infection depend on the malicious program's abilities and the cyber criminals' modus operandi. Smoke Loader is a loader-type malware – it is designed to cause chain infections. Hence, its presence on a device can lead to multiple system infections, severe privacy issues, financial losses, and identity theft.

What is the purpose of Smoke Loader malware?

In general, the most prevalent reason for such attacks is financial gain. However, cyber criminals can also use malicious software to amuse themselves, realize personal grudges, disrupt processes (sites, services, etc.), engage in hacktivism, and launch politically/geopolitically motivated attacks. It is pertinent to mention that Smoke Loader has been used to conduct geopolitically driven cyber espionage.

How did Smoke Loader malware infiltrate my computer?

Malware is primarily distributed via spam emails/messages, drive-by downloads, online scams, malvertising, untrustworthy download sources (e.g., freeware and third-party sites, Peer-to-Peer sharing networks, etc.), illegal software activation tools ("cracks"), and fake updates. Some malicious programs can self-spread through local networks and removable storage devices (e.g., USB flash drives, external hard drives, etc.).

Will Combo Cleaner protect me from malware?

Combo Cleaner can detect and eliminate practically all known malware infections. It must be stressed that performing a full system scan is crucial since high-end malicious software typically hides deep within systems.