How to remove Atomic Stealer (Mac)

What is Atomic Stealer

Atomic Stealer, also referred to as AMOS or Atomic macOS Stealer, is a type of information-stealing malware that specifically targets macOS devices. It emerged around April 2023 and has since been actively updated by its developers. The malware is designed to exfiltrate a wide range of sensitive data, including cryptocurrency wallet credentials, browser data, system information, and other passwords stored on the infected device. The inception of Atomic Stealer can be traced back to early 2023, when cybersecurity researchers first documented its presence. Initially advertised on Russian hacking forums, the malware was offered for a monthly subscription fee, indicating a professional level of development and distribution. Over time, Atomic Stealer has evolved, incorporating sophisticated encryption techniques to evade detection and employing various distribution methods to widen its reach. This article delves into the nature of Atomic Stealer, its infection process, methods for removal, and strategies for prevention, providing a comprehensive overview of this cybersecurity menace.

How Atomic Stealer infected your system

Atomic Stealer employs several vectors to infect macOS devices, with malvertising and fake software updates being among the most prevalent. Malvertising involves the use of malicious advertisements to redirect users to websites that distribute the malware. These ads often appear in search engine results, exploiting the trust users place in these platforms. Fake software updates, on the other hand, trick users into downloading and installing the malware by masquerading as legitimate updates for popular applications or browsers. Once downloaded, Atomic Stealer leverages a combination of Python scripts and AppleScript to execute its malicious activities. It often displays a fake dialog box asking for the system password, which, if entered, grants the malware the necessary permissions to access and steal files and data stored in the iCloud Keychain and browsers.

Remove Atomic Stealer from macOS manually

Removing Atomic Stealer from macOS requires a systematic approach that involves a combination of built-in tools, safe computing practices, and sometimes third-party software. Here’s a comprehensive guide to identifying and removing viruses from your Mac, ensuring your system’s integrity and security.

Step 1: Disconnect from the Internet

1. Disconnect your Mac from the Internet. This prevents the virus from sending data to its creator or downloading more malicious software. Turn off Wi-Fi and unplug any Ethernet cables.

Step 2: Enter Safe Mode

2. Restart your Mac in Safe Mode. Safe Mode performs a check of your startup disk and restricts certain software from automatically loading or opening.
   • For Intel-based Macs: Restart your Mac and immediately press and hold the Shift key until you see the login window.
   • For Apple Silicon Macs: Turn off your Mac, press and hold the power button until you see the startup options window, select your startup disk, press and hold the Shift key, then click Continue in Safe Mode.

Step 3: Use Built-in Tools for Malware Removal

3. Use Finder to identify and remove suspicious applications.
   • Open Finder, go to the Applications folder, and look for any applications you don’t recognize or didn’t intentionally download.
   • Right-click the suspicious application and select Move to Trash, then empty the Trash.
4. Use macOS built-in malware removal tool (MRT). macOS automatically runs MRT in the background, but you can manually run a malware scan by updating your software.
   • Go to System Preferences > Software Update.
   • Install any available updates, as these often include the latest security improvements and malware definitions.

Step 4: Check and remove Atomic Stealer from Login Items

Note: Atomic Stealer may set up to start on macOS startup. Therefore, before starting the removal, perform these steps:

1. Open System Preferences, choose Users & Groups.
2. Choose your account (set up as Current User).
3. Click Login Items tab.
4. Find suspicious entries. Select it, and click the “-“ (minus) button to remove them.

Step 5: Check and remove Atomic Stealer Malicious Device Profile

Important update: Atomic Stealer can install malicious Device Profile called AdminPrefs or similarly on MacOS, that won’t allow users to make changes to browser search engine and homepage settings. Follow instructions below to remove this profile.

Remove Atomic Stealer profile

1. Go to System Preferences and click on Profiles.
2. In the list of profiles on the left side, choose AdminPrefs or other profile and click on “-” button to remove it.
3. In your case it can be named differently, in this case remove all visible profiles. Check the picture below to see how it looks like.

Step 6: Reset Your Web Browsers

Reset Safari:

1. Start Safari on your Mac, click Safari to open drop-down menu and choose Preferences
2. Go to the Privacy section of Safari’s preferences.
3. Click Remove All Website Data button.
4. In the opened window, click Remove Now button to remove data stored by websites in Safari.
5. Go to the Advanced section of Safari’s preferences.
6. Click the Show Develop menu in menu bar option.
7. In the menu, click Develop and select Empty Caches from this menu.
8. Again, go to Safari menu and choose Clear History….
9. Choose to clear all history and click Clear History button.

Reset Google Chrome:

1. Start Google Chrome browser
2. In address box type (or copy-paste) chrome://settings.
3. Scroll down and find Show advanced settings link.
4. Click on it and scroll down to the bottom again.
5. Click Reset settings button and click Reset to confirm.

Reset Mozilla Firefox:

1. Start Mozilla Firefox browser.
2. In address box type (or copy-paste) about:support.
3. Click Refresh Firefox… button.
4. Click Refresh Firefox to confirm.

Step 7: Restore from a Backup

8. If the issue persists, consider restoring your Mac from a backup.
   • Use Time Machine or another backup system to restore your Mac to a state before it was infected.
   • Ensure the backup you choose predates the malware infection.

Prevention Tips

• Keep your macOS updated. Regularly check for and install macOS updates to ensure you have the latest security patches.
• Be cautious with downloads and attachments. Only download software from trusted sources like the Mac App Store or official websites.
• Use strong passwords and enable two-factor authentication (2FA) where possible.
• Consider enabling the macOS firewall in System Preferences > Security & Privacy.
• Regularly back up your Mac using Time Machine or another backup solution to ensure you can recover your system if needed.

Following these steps should help you remove most viruses from your Mac. If you continue to experience issues, consider seeking help from Apple Support or a professional cybersecurity service.