How to remove RustBucket Malware (Mac)

What is RustBucket Malware

RustBucket is a sophisticated macOS threat known for its ability to download additional payloads from a Command-and-Control server, posing significant risks to infected systems. By stealthily infiltrating a computer, it collects sensitive data such as login credentials and personal information, potentially leading to identity theft and financial fraud. This malware is capable of executing remote commands, which allows attackers to modify or delete files, install further malicious software, or even control the system remotely. Its distribution often involves social engineering techniques, where unsuspecting users are tricked into overriding macOS security measures like Gatekeeper to execute the malicious payload. Once embedded within the system, RustBucket can evade detection by traditional security solutions due to its advanced anti-detection features. This makes it a formidable threat, as it not only compromises user privacy but can also cause data loss and system instability. Keeping macOS updated and using reputable security software are crucial steps in preventing such infections.

How RustBucket Malware infected your system

RustBucket malware infiltrates computers through a sophisticated multi-stage process that leverages social engineering tactics to deceive users. The infection begins with an unsigned application named “Internal PDF Viewer.app,” which users are tricked into downloading and executing by manually overriding macOS’s Gatekeeper. Once launched, this app retrieves a secondary payload, a signed application masquerading as a legitimate software bundle, which displays a fake PDF document to the user. This document is often crafted to appear as information from a credible source, such as a venture capital firm, to lower suspicion. Upon execution, the malware communicates with a Command-and-Control (C&C) server to download a third-stage payload, a Trojan developed in the Rust programming language, capable of running on both ARM and x86 architectures. This final payload allows attackers to execute various harmful actions, including data theft and system manipulation, making RustBucket a particularly dangerous threat to macOS users.

Remove RustBucket Malware from macOS manually

Removing RustBucket Malware 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 RustBucket Malware from Login Items

Note: RustBucket Malware 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 RustBucket Malware Malicious Device Profile

Important update: RustBucket Malware 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 RustBucket Malware 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.