How do I know if my Mac has a virus? Do you think a virus or malware could infect your Mac? Have you noticed that the computer is not behaving as it should, and do you think it could be due to an infection? In the following article, you will find help to detect if the problem is this and some tips to solve it.
You can also read: Best Antivirus for Mac: Best Options in 2021
Surely you have heard on many occasions that Apple products do not receive malware or virus attacks. This is a half-truth since there has always been this type of malicious software for Mac, but due to its smaller presence in the market and its greater native security, the attacks were much more limited.
Currently, the market share of computers with macOS (the operating system of Macs formerly known as OS X) is much larger, and attackers are putting more and more effort into attacking the system. Despite this, there have been no malware or virus attacks as large as in Windows, but the risk of being infected exists. That is why we have decided to create this guide with tips to keep Macs safe and remove viruses and malware in case of infection.
I will discuss viruses and malware throughout the article without making distinctions, although the differences are significant. The former are snippets of code designed to perform tasks entirely invisibly on infected computers. In contrast, the latter is usually disguised as applications that promise to do one thing but do others, such as stealing user data (one of the best-known malware for Mac is MacKeeper that disguises itself as maintenance software for the computer).
How to detect if my Mac is infected
Before removing any viruses or malware, it is essential to determine if your computer is indeed infected. To do this, having a series of basic knowledge about computer security is necessary. In addition, knowing some common symptoms such as the following can be of great help:
- Your Mac starts running slowly in everyday use, as if some application is consuming all the resources.
- Safari, Chrome or any other browser show a new toolbar that wasn’t there before and you don’t remember installing it. Generally these bars have buttons or forms to search or access online shopping websites.
- When doing searches on Google or other search engines you are redirected to websites that you do not know or to fake versions of official websites (it is easy to recognize them by looking at the URL to which they send you).
- All the websites you visit have overlapping ads, even pages where there is no advertising (Wikipedia for example).
- Favorites don’t work and when you try to access it it sends you to unknown pages.
- Ad-supported windows open suddenly, even when you’re not browsing the Internet or using an app.
If your computer has any of these symptoms, you may begin to suspect, especially those related to browser hijacking or the appearance of random advertising windows. If the only symptom you detect is that the Mac starts to work slower, it may be a simple failure of some software installed.
If you’ve reviewed the tips above and still think your Mac is infected, don’t directly Google how to remove a particular virus or malware. Most likely, you will arrive at websites that recommend software to remove it. Another malware disguised as security software (one of the most prominent examples is MacDefender, without forgetting the MacKeeper mentioned above).
These pages are usually compelling. They are designed only to defraud users and for attackers to expand their infected network. In short, they are designed to get the money of the people who have been affected and who are looking for a solution to their problem.
How malware gets to Mac
There are several ways in which malware reaches Macs. If you suspect that you are infected, remember and try to remember you have had a run-in with any of the things in the following list:
1. Malicious software
As mentioned before, the malware often comes hidden in legitimate software, but it is nothing more than a disguise to hide the malicious application. Maintenance software, fake antivirus, and even games are some of the resources used by attackers.
To avoid ending up infected in this way, it is best to avoid installing any program that you are not 100% sure of, and when in doubt, consult with other people if they have used it, and it is recommended. You can turn to specialized forums or blogs to help you.
2. Fake files
Sometimes malware and viruses masquerade as images, text, or PDF files. This method of infection is quite effective in users with little knowledge.
The best recommendation is that you avoid opening any file that appears on your computer’s desktop or in a folder and does not know its origin.
3. Legitimate software with malware
Malware and viruses can take advantage of security flaws in macOS or any program installed on your computer to sneak in. For example, they can take advantage of Safari security flaws to run on your computer when visiting an infected web page or similar.
In addition, it is also quite common for attackers to integrate their malicious software inside legitimate software installers to infect users when they install it.
In this case, the best recommendation is too cautious when browsing and not to access websites that may seem suspicious. Also, avoid installing software on your computer that you do not know its origin. Much less, install pirated software downloaded from any website since you do not know if it has been modified to include viruses or malware.
4. Fake updates or system tools
While browsing the Internet, it is pretty standard that windows appear that announce fake antivirus or fake updates of Flash or other add-ons for the browser. In this case, you should close those windows without consideration and avoid installing the software they offer since it is most likely some malicious software.
5. False technical assistance
Related to the previous point, sometimes you can see warnings that ensure that your Mac is infected by a virus and offer you software to clean it. If you accept and install the software, you will be infecting your computer with malware that can have different targets.
As in the previous point, immediately close the window that shows you that warning and never install anything without being 100% sure it comes from a reliable source. It does not hide secrets that can damage your computer.
macOS offers a certain level of protection natively
For several generations of macOS (formerly known as Mac OS X), the operating system integrates a certain level of protection against malware and viruses. The central protection systems are as follows:
Gatekeeper and file quarantine
When you open an application for the first time, you will see a window that tells you its origin and the date on which it was downloaded. If you agree, you will be able to open it with the accept button that appears in that window (the only exception to this is the applications downloaded from the Mac App Store, since they have been reviewed by Apple and are trusted by the company).
Also, if an application is not signed by the creator and recognized by Apple, you will not install it on your Mac.
This macOS feature scans downloaded files when they are first run. If you locate any known virus or malware, it will only show the option to move it to the trash.
Xprotect has been very effective in stopping the spread of malware attacks on Mac. Thanks to this security system, attacks were mitigated very quickly and is another reason why attackers still do not focus too much on Macs when carrying out their attacks. It is too difficult for them to infect a large number of computers.
How to Remove Viruses and Malware on Mac
Do you think some malware or viruses infect your Mac after reading all the above information? If so, here are 10 tips with which you can prevent the damage of the infection from being more essential and how to obliterate the malicious software.
1. Do not write more passwords
If you think you’re infected, try not to type in any of your passwords. It is common for attackers to introduce hidden keyloggers to steal passwords and know everything you type.
Also, you shouldn’t open documents with sensitive information or passwords to copy and paste. These keyloggers can take screenshots from time to time and send them to attackers, so they would eventually have access to them even if you’re not typing them with the keyboard.
2. Disconnect your Mac from the Internet
Most malware is dedicated to stealing data from your computer or using its resources to perform specific tasks (attacks on other networks, cryptocurrency mining, etc. That is why limiting the Internet connection can prevent further problems since attackers will not be able to access the data or resources of the computer.
Remove the ethernet cable if you connect over a wired network or disconnect the WiFi network in case of wireless networks, and do not connect the computer again until you are sure that the disinfection is complete.
3. Check the Activity Monitor
Run Activity Monitor from Applications – Utilities and review the list of running tasks. You may see that some process is consuming more resources than it should, or you may know some software that shouldn’t be running and that you think maybe malware.
In this case, click on the process in the list and close it completely using the X icon, the first in the Activity Monitor toolbar.
4. Turn off the computer and restore a backup copy
If you think your Mac is infected and you know the moment it has occurred (you remember having installed software of dubious origin or accessed some supposed security software that recommended an advertisement from a website), restoring a previous backup can be a good solution.
Restore to the moment before infection through Time Machine or the backup software you use. Also, avoid connecting any removable drive connected during the infection and try to clean it with a Windows PC with updated antivirus software (although the virus is for Mac, antivirus usually detects malicious software intended for other operating systems).
5. Pass a software to clean malware or viruses
In the market, there are different solutions to clean any Mac from viruses and malware. Most of them are effective and excellent tools to facilitate the cleaning of any malicious software that infects your computer.
Once the antivirus is installed, it updates the virus definition database and performs the most comprehensive scan available to the software. This will ensure that it searches profoundly and removes all malware that it can recognize.
This analysis likely involves several hours of waiting, but if you want to stay calm, it is highly recommended that you give it a good dose of patience.
6. Watch out for your credit card details
If you think that your Mac has been infected by a file or application that you have located, the first thing is to move it to the trash and empty it thoroughly to remove the source of the infection from the computer.
Also, if to get that file you made any payment, for example, falling into the trap of fake antivirus software, contact your bank immediately. Explain the situation to them and tell them what steps to take. You probably can’t get your money back, but your card will likely be blocked, and a new one sent to prevent them from using the old one fraudulently or at least increasing the monitoring of your account movements.
7. Clear the cache of the computer and browsers
Another important point when cleaning a virus or malware infection is to clean the cache of the Mac and the browsers installed on it.
In this article, you can see How to Clear Cache on Mac and Recover a LOT of Storage Space, and you can also check the preferences section of the browsers to clean them (the process is a little different in each one).
8. Empty the Downloads folder
The Downloads folder is usually the location where all the files you download through the browsers installed on your computer go. These are usually the origin of most viruses and malware.
Go to the Downloads folder, select everything inside and drag it to the trash. Finally, empty the trash can so as not to trace any possible source of infection.
9. Change all passwords
Once you believe that the infection has been thoroughly cleaned, it is recommended that you change all your passwords. We talk about all of them, from that of the user of your Mac to others, such as access to your email, electronic banking, web services, etc.
10. Reinstall macOS
If, after doing all of the above, you still have doubts and think that the malware or virus could continue on your Mac, the best thing you can do is reinstall macOS from scratch. In addition, it is best to completely erase the hard drive or SSD via Disk Utility before starting the macOS reinstallation process.
This way, you delete EVERYTHING in the storage system of the Mac and reinstall it from scratch so that the malicious software will disappear without any doubt as well.
You can also read: Best Antivirus for Mac: Best Options in 2021