How to remove Ave Maria malware from the operating system

What kind of malware is Ave Maria?

Ave Maria is high-risk trojan designed to steal various information and to cause "chain infections" (spread other infections). It is typically proliferated using various spam email campaigns.

Criminals send thousands of deceptive emails that contain infectious attachments, most of which are Microsoft Office (typically Excel) files. Emails are delivered with messages encouraging users to open the attached document, however, this results in infiltration of Ave Maria.

More about emails distributing Ave Maria

One of the emails we examined was an order confirmation, which contained an "invoice" attached. The message essentially states that information regarding a type of order is provided in the attached document and encourages users to review it. This, however, results in a malware infection.

This particular email was supposedly sent by an employee of the Mignon Sista International company, however, this is a deceptive tactic - cyber criminals often claim to be employees of popular companies or governmental agencies to give the impression of legitimacy, since users are much more likely to open attachments that are received from familiar names.

More about Ave Maria

Developers of this virus often target small companies/businesses, rather than regular users. Therefore, most recipients are employees/owners of various companies and businesses. This, however, does not mean that regular users are safe. The Ave Maria virus is designed to track information and record victims' keystrokes.

These infections are used to gather personal information, such as logins/passwords (of emails, social networks, etc.), credit card information, and so on. Having such information stolen is very risky. Cyber criminals aim to generate as much revenue as possible. Therefore, they are likely to misuse stolen accounts.

If they gain access to bank accounts, they can steal all funds by transfer to their accounts or via online purchases. Emails, social networks, and other accounts can be used to steal identities and perform various malicious actions (e.g., send malware to victims' contacts, ask contacts to lend money, and so on). Additionally, Ave Maria injects the system with additional malware.

At the time of research Ave Maria was used to proliferate another data-stealing trojan called LokiBot. However, the list of Ave Maria's features includes download and execution of files, which means that the situation might (and probably will) eventually change and crooks will use Ave Maria to spread some other malware.

Typically, trojans are used to proliferate ransomware and cryptominers. It is rather uncommon for trojans to spread viruses that have similar functionality (like in this case both Ave Maria and LokiBot are designed to steal data). Typically trojans spread infections that behave have different features.

It is also worth mentioning that depending on Ave Maria's variant (executable) its process name is in Windows Task Manager is different. However, it is known that Ave Maria typically hides behind names of various genuine processes (e.g., "Firefox", "svchost.exe", etc.) in order to hide its presence.

What's interesting is that Ave Maria processes' icons are not genuine (e.g., "Firefox" process icon is some blurry square, rather than the original icon which is a fox winded around the globe). This allows to distinguish the fake processes.

Moreover, this malware is designed to alter Windows Defender's settings and prevent it from scanning the entire disk that Windows are installed in (typically its C:\ disk). That's because Ave Maria's files are hidden in Windows directory (there are few duplicates, one of them is hidden in "%APPDATA%" folder) and adds a Windows registry entry.

You can see the full list of Ave Maria's features below. In summary, having this virus on your computer can lead to various privacy issues, financial losses, and high-risk computer infections. As mentioned above, Ave Maria's process can be found in Windows Task Manager under random name.

If you find any dubious processes running, and suspect Ave Maria's presence, immediately scan your computer with a reputable anti-virus/anti-spyware suite and eliminate all detected threats.

Similarities with other trojan-type malware

Ave Maria shares many similarities with a number of other trojan-type viruses, such as TrickBot, Adwind, FormBook, and Qakbot.

Although these viruses are developed by different cyber criminals, all have the same purpose: to steal personal data. In addition, as with Ave Maria, these viruses are often distributed using spam email campaigns. They pose a significant threat to users' privacy and financial safety. Therefore, eliminating malware such as Ave Maria is paramount.

How did Ave Maria infiltrate my computer?

As mentioned above, Ave Maria is distributed using spam email campaigns that contain malicious MS Office documents attached. In most cases, the attachment format is Excel, which exploits an MS Office vulnerability (code-name CVE-2017-11882) to inject Ave Maria into the system.

This is a common method to proliferate trojans such as Ave Maria, however, the attachment is not always an MS Office document - the file type might be different (e.g., PDF, JavaScript, .exe, archive, or other).

In any case, user interaction is necessary for the malware to infiltrate the system. The user must manually run/open the attachment, otherwise the virus cannot enter the system.

How to avoid installation of malware?

To prevent this situation, be very cautious when browsing the internet. Think twice before opening email attachments. If the sender seems suspicious/unrecognizable or the attached link/file is irrelevant, do not open anything.

Bear in mind that criminals often try to abuse the recipient's curiosity by sending fraudulent messages, such as "you have received a package", "you have won a lottery", and so on. Unfortunately many users fall for these scams, hoping that they have gained something free of charge. Therefore, you should never trust such messages.

Have a reputable anti-virus/anti-spyware suite installed and running, since these programs commonly detect and eliminate malware before any damage is done. Lack of knowledge and careless behavior are the main reasons for computer infections. The key to safety is caution.

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.

List of Ave Maria trojan's features:

• Camera Exfiltration
• Cleanup
• Code Injection
• Download and Execution
• File Management: creation, download, exfiltration, deletion
• Info-stealer support:
  Firefox
  Foxmail
  Google Chrome
  Internet Explorer
  Outlook
  Thunderbird
• Offline Keylogger
• Persistence
• Privilege Escalation, support from Windows 7 to Windows 10
• Processes Management: enumeration, termination
• RDP using rdpwrap

Examples of rogue processes ("apo.exe" and "Firefox") of Ave Maria in Windows Task Manager:

Examples of a malicious MS Word documents designed to inject Ave Maria trojan:

Another example of a spam email used to spread Ave Maria trojan (the attachment is a .r00 archive containing a malicious executable):

Text presented within:

Dear Sirs,

Please find attached debit note for payment reference as we need to reconcile all this week.

Waiting your soonest response.

Thanks for your understanding ..

Update September 7, 2020 - New spam campaigns proliferating the Ave Maria trojan have been detected. The scam emails (titles/subjects "Re: Consignment Notification: You have A Package With Us", "TNT ARRIVAL NOTIFICATION REPORT / INVOICE & BILL"; may vary) distributed though these campaigns are disguised as package delivery notifications from legitimate courier companies (e.g. DHL, TNT Express, etc.).

The infection chain is initiated when recipients open decoy images of fake invoices, which contain embedded URLs. Once the images are clicked on, virulent files are downloaded and automatically executed. The infectious files are hosted on Discord - instant messaging and VoIP application.

Should the Discord app be installed and/or open on the targeted device - spam filters and endpoint protection systems might be unable to detect that the URLs are malicious and simply allow all links from Discord.

Example of yet another spam email used to spread Ave Maria trojan (the attachment is a .7z archive containing a malicious executable):

Text presented within:

Subject: New order - 04.01.2021 2X40' 1/5/2021 9:56:39 a.m.

Good Morning All and a Happy New Year,
 
Hope your doing well.
Please refer attach file.
File Password: Password123
 
This is for contract order projects for our customer.
Could you let me know product ready date?

We want to receive this container till mid of March 2021.
(Port to Tokyo by 20ft)
 
Also, I want to add order some other products.
(I will send to you PO this Thursday)
 
Please let me know ready date of this attach qty first.
If you have any question, Please let me know.
 
Thank you for your cooperation.
 
======================================
- -
Vice President, - Co., Ltd.
Seoul, Korea
T; +82 -
F; +82 -
M; +82 -
E; -

======================================
CONFIDENTIALITY NOTICE
This e-mail and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed.  If you have received this e-mail in error please delete the e-mail and any attachment(s) and notify the sender.  This footnote also confirms that this e-mail message has been scanned for the presence of computer viruses.
Please consider the environment before printing this E-Mail.

An example of a malicious MS Excel document (distributed via spam emails) designed to inject Ave Maria trojan into the system:

Another example of a spam email spreading Ave Maria trojan:

Text presented within:

Subject: RE: EQUIRY ORDER

 

Hello Dear,

Hope this email find you in good health. My company will love to start a long term business relationship with your company as we have visited your site. You will find the attached  Purchase order and  and description of the goods  Order, Kindly see attached.

and quote me your best offer and deliver time.If your offer is okay for us,we will confirm the Order according to the quotation.Note that our company do not allow 50% deposit.We will pay 30% TT and the rest Against BL.We hope to have this chance to corporate with  you and build a long term business relationship with your company. Any question,please feel free to contact me.

Looking forward for your kind reply

Best Regards

Yassin Bakach
CMD TAX
Boekhouding & Fiscaliteit
Hof Ter Lo 6B
2140 Borgerhout
Tel: +32(0)3 663.17.07
Gsm: +32(0)484 82.81.11
E-mail: info@bctax.be

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

No, there is no need to perform this procedure.  Malware like Ave Maria can be removed without formatting the storage device.

What are the biggest issues that malware can cause?

It depends on the capabilities of the malware. Usually, cybercriminals use it to steal money, personal accounts, identities, distribute other malware, mine cryptocurrency, or encrypt files.

What is the purpose of Ave Maria malware?

Ave Maria collects sensitive information (like credit card details, login credentials, etc.). It also can infect a computer with additional malware. We found that threat actors have used Ave Maria to distribute LokiBot.

How did a malware infiltrate my computer?

It is known that Ave Maria malware is distributed via email. Threat actors send emails containing malicious attachments designed to infect computers with Ave Maria. Malicious MS Office documents infect computers after users enable macros commands (editing/content).

Will Combo Cleaner protect me from malware?

Yes, Combo Cleaner can detect and remove almost all known malware from the operating system. If a computer is infected with high-end malware, it is required to run a full system scan to remove that malware. High-end malware usually hides deep in the operating system. Thus, running a quick scan is not enough to detect and remove it.