Introduction
Macs have long maintained a reputation for their robust security features, which make them less susceptible to viruses and malware when compared to their Windows counterparts. However, no computer is entirely immune to cyber threats, and Macs can still fall victim to viruses and other malicious software. If you suspect your Mac computer has been infected, you need to act quickly and follow a systematic procedure to minimize damage and restore your system’s health. In this article, we’ll outline a step-by-step guide on what to do when you have to deal with a virus infected Mac computer.
Isolate Your Mac
The moment you suspect a virus infection, disconnect your Mac from the internet. This can help prevent the virus from spreading or communicating with its command and control servers. Additionally, disable any network shares or file-sharing features to prevent further transmission of the malware.
Backup Your Data
Before attempting to remove the virus, it is essential to ensure that you back up your important files and data, if possible. You can achieve this by utilizing an external hard drive or opting for a cloud-based backup service, such as iCloud or Dropbox.
This precautionary measure is crucial because virus removal procedures can occasionally result in data loss. Additionally, it’s important to be mindful that during the process, you might inadvertently spread the virus to your backup device. Consequently, the virus has the potential to render your computer useless until it is successfully eliminated. Therefore, the backup method may not be the most suitable choice in certain situations.
Identify the Symptoms
Try to identify the symptoms of the virus infection. Common signs of a virus-infected Mac include sluggish performance, unexpected crashes, unusual pop-up messages, and changes to your browser’s homepage or search engine. Knowing the specific symptoms can help you narrow down the type of malware and find an appropriate solution.
Use Built-in Mac Security Tools
MacOS comes equipped with several built-in security features to help you combat viruses and malware. Start by updating your operating system to the latest version, as updates often include security patches. Then, run a full system scan using the built-in macOS antivirus tool called “XProtect” or “Gatekeeper.” To perform this action, navigate to “System Preferences” > “Security & Privacy” > “General,” and select the “Mac App Store and identified developers” option under “Allow apps downloaded from.”
Install a Reliable Antivirus Software 
While macOS has decent built-in security features, it’s still advisable to install reputable antivirus software, even if you’ve resolved the current issue. These programs can provide real-time protection against future threats. Popular antivirus options for Mac include Bitdefender, Norton, Malwarebytes and Avast Security.
Quarantine and Remove Malicious Files
If your built-in or third-party antivirus software identifies malicious files or applications, follow the prompts to quarantine and remove them. Be cautious and only delete files that are confirmed to be threats. Avoid manually deleting system files, as this can lead to instability.
Check for Browser Extensions
Many viruses and malware target web browsers. Check your browser for any suspicious extensions or plugins. Remove any that you didn’t intentionally install. You may also want to reset your browser settings to their default state to ensure all changes made by the malware are reversed.
Monitor Your System
After removing the virus, keep a close eye on your Mac’s performance. Ensure that your antivirus software is running regular scans and updating its virus definitions. Also, practice safe browsing habits and avoid downloading files or clicking on links from questionable sources.
Update Your Passwords
If you suspect that someone may have compromised your online accounts, immediately change your passwords. Use strong, unique passwords for each account and consider using a password manager to keep them secure.
Review Recent Downloads and Installations
Examine your recent downloads and installed applications. If you notice any suspicious files or software that you don’t remember intentionally downloading or installing, remove them immediately.
Check for Unusual Network Activity
Monitor your network activity to see if there are any suspicious outgoing connections or unusual data usage. You can use built-in macOS tools like Activity Monitor to check network activity or consider using a network monitoring tool for more detailed information.
Inspect Email and Messaging Apps
Viruses can sometimes spread through email attachments or malicious links. Review your email accounts and messaging apps for any suspicious messages, especially those from unknown senders. Delete any suspicious emails and empty your email trash folder.
Examine System Logs
macOS keeps logs of various system events. Checking these logs for unusual or suspicious entries can help identify the source and behavior of the virus. To access system logs, go to the “Console” application in the “Utilities” folder within the “Applications” folder.
Run a Rootkit Detector
This is a more advanced solution for system administrators. Rootkits are a type of malware that can be particularly stealthy and hard to detect. Consider running a rootkit detector such as rkhunter or CHKRootKit to scan for these types of infections.
Review Firewall Settings
Ensure you enable and configure your Mac’s firewall correctly. You can check and configure your firewall settings in “System Preferences” > “Security & Privacy” > “Firewall.” This can help prevent unauthorized access and communication from malicious software.
Please remember that if you are unsure about any of these steps or if you believe your Mac still has an infection after performing these checks, it’s advisable to consult with a professional computer technician or IT specialist. They can offer expert assistance in thoroughly diagnosing and removing the virus from your system.
Reinstall or Update Your Mac OS
If you encounter a severe virus infection, it may require you to update or reinstall macOS. Certain viruses have the potential to corrupt or modify essential system files, necessitating a system software reinstallation. To address such situations effectively, it is highly recommended to possess a bootable macOS USB flash drive that matches your Mac’s operating system.
For further insights and guidance on acquiring and utilizing a bootable macOS USB flash drive for your Mac, we recommend referring to the article titled “macOS Bootable Recovery USB.” This resource provides valuable information on the process.
For a selection of macOS Bootable Recovery USB flash drives visit the Mac Medic Store.
Conclusion
Discovering a virus on your Mac can be a stressful experience, but with a systematic approach, you can effectively remove the threat and safeguard your system. By isolating your Mac, backing up your data, using built-in security tools, installing reputable antivirus software, and following the steps outlined in this guide, you can regain control of your Mac and protect it from future threats. Remember that staying proactive in your cybersecurity practices is key to maintaining a safe and secure computing environment.
Article 121: MacMedicStore.com