How to remove VShell Malware (Mac)

What is VShell Malware

VShell Malware is a sophisticated form of malicious software that operates as a backdoor and Remote Access Trojan (RAT), specifically designed to infiltrate systems stealthily. It functions primarily in-memory, making it difficult for traditional antivirus programs to detect, as it leaves no traceable files on the system. By disguising itself as legitimate processes, VShell can execute arbitrary commands, allowing attackers to gain unauthorized remote access and control over infected devices. This malware is notorious for its ability to introduce additional payloads, potentially leading to chain infections that may include trojans, ransomware, or other harmful software. The presence of VShell on a system can result in significant privacy breaches, including data theft and unauthorized access to sensitive information, which may lead to financial losses and identity theft. Additionally, VShell has been linked to state-sponsored cyber-espionage activities, posing a severe threat to targeted industries such as government, defense, and technology. Users are advised to employ robust security measures and regularly update their software to mitigate the risks associated with such advanced malware.

How VShell Malware infected your system

VShell malware is a sophisticated and highly adaptable threat, capable of infiltrating systems running macOS, Windows, and Linux through a variety of deceptive techniques. This fileless malware executes in-memory, leveraging the “fexecve” system call to disguise itself as a legitimate system process, which evades traditional file-based detection methods. Cybercriminals often distribute VShell through malicious email attachments, compromised online advertisements, and social engineering tactics, enticing users to open seemingly innocuous files that trigger the malware’s installation. This malware has been used by the Chinese state-sponsored group UNC5174, which customizes its distribution methods, including phishing campaigns and exploiting software vulnerabilities, to target entities in critical sectors. Once infiltrated, VShell operates as a backdoor, enabling remote access and control, downloading additional malicious payloads, and injecting harmful code to further compromise the infected system. The ability of VShell to cause chain infections and exfiltrate sensitive files makes it a significant threat, leading to severe privacy breaches, financial losses, and potential identity theft.

Remove VShell Malware from macOS manually

Removing VShell 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 VShell Malware from Login Items

Note: VShell 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 VShell Malware Malicious Device Profile

Important update: VShell 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 VShell 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.