How to Check for Malware on Mac: A Complete Guide

Macs have a strong reputation for security, but that reputation has made them a more attractive target over time. As the Mac user base has grown, so has the volume of malware specifically written for macOS. Knowing how to check for malware on your Mac — and understanding what you're actually looking for — is a practical skill every user should have.

Does Mac Get Malware?

Yes. The idea that Macs are immune to malware is outdated. Modern threats targeting macOS include adware, spyware, Trojans, ransomware, and browser hijackers. Many of these don't look like traditional viruses — they arrive disguised as legitimate software, browser extensions, or system utilities.

Apple builds several layers of protection into macOS — including Gatekeeper, XProtect, and Notarization — but these are not a complete substitute for awareness and periodic manual checks.

Signs Your Mac May Be Infected

Before running any scans, watch for behavioral red flags:

• Unexpected slowdowns — your Mac is sluggish even when few apps are open
• Browser changes you didn't make — new homepage, unfamiliar extensions, or redirected searches
• Pop-up ads appearing outside of any browser window
• Apps launching on their own or processes you don't recognize running in the background
• Unusual network activity — data being sent or received at odd times
• Antivirus or system settings that won't respond — some malware actively disables defenses

None of these symptoms confirms malware on their own, but a cluster of them warrants a closer look.

How to Check for Malware on Mac Manually

1. Review Login Items and Launch Agents

Malware often persists by adding itself to startup processes. Check two places:

Login Items: Go to System Settings → General → Login Items. Review anything listed under "Open at Login." Remove anything you don't recognize.

Launch Agents and Daemons: These are folders where background processes live. Navigate in Finder using Go → Go to Folder and check:

• /Library/LaunchAgents
• /Library/LaunchDaemons
• ~/Library/LaunchAgents

Look for .plist files with unfamiliar names, especially those referencing strings of random characters or names that mimic legitimate system files.

2. Check Activity Monitor

Open Activity Monitor (found in Applications → Utilities). Sort processes by CPU or Memory usage. Look for:

• Processes consuming unusually high resources
• Names you don't recognize that aren't standard macOS processes
• Duplicate or oddly named versions of common system tools

You can Google any suspicious process name directly — this is one of the fastest ways to determine whether something is legitimate.

3. Review Browser Extensions

Browser hijackers frequently hide inside extensions. In each browser you use:

• Safari: Settings → Extensions
• Chrome: chrome://extensions
• Firefox: about:addons

Disable or remove anything you didn't deliberately install. Even extensions from recognizable-looking names can be problematic if they appeared without your action.

4. Check the /Applications Folder

Open your Applications folder and scroll through. Unfamiliar apps — especially ones with names that sound like system utilities ("Mac Cleanup Pro," "Advanced Mac Cleaner") — are a common sign of adware or potentially unwanted programs (PUPs). These often aren't technically malware but behave in ways that compromise your experience and privacy.

Using Built-In macOS Protections

macOS includes XProtect, a signature-based malware detection tool that runs silently in the background. It updates automatically and doesn't require any user interaction. However, XProtect works reactively — it catches known threats based on signatures — which means it won't catch brand-new or novel malware until Apple updates its definitions.

Malware Removal Tool (MRT) is another Apple utility that runs periodically and removes known malware infections automatically. Again, this runs without user input.

These tools provide a baseline — but they're not a comprehensive solution, especially against newer or more sophisticated threats.

Third-Party Malware Scanners 🔍

A range of third-party security tools exist for macOS. When evaluating them, the variables that matter include:

Well-regarded categories of tools include dedicated Mac antivirus software, on-demand malware scanners, and network monitoring utilities — each catches different types of threats. A user running an older MacBook on an unsupported macOS version has meaningfully different options than someone on a current Apple Silicon Mac with the latest OS.

What to Do If You Find Something

If you identify a suspicious process, app, or file:

1. Don't panic and don't pay — if a pop-up is demanding payment or threatening you, this is almost certainly a scam
2. Quit the process in Activity Monitor before attempting removal
3. Move the app to Trash and empty it — then check Login Items and LaunchAgents to remove any associated persistence files
4. Reset your browser settings if extensions or homepage were changed
5. Change passwords for any accounts accessed during the period your Mac may have been compromised, especially banking or email

For persistent infections that survive manual removal, a bootable macOS recovery or clean install may be necessary. 🛡️

The Variables That Shape Your Risk Profile

How aggressively you need to check — and what tools make sense — depends on factors specific to your situation:

• What you download and from where — App Store apps go through review; software from third-party sites carries more risk
• How many users share the Mac — shared machines have more exposure
• Your macOS version — older versions receive fewer XProtect updates and may lack newer security features
• Whether you use public Wi-Fi — increases exposure to network-based threats
• Your technical comfort level — manual checks require some familiarity with system folders and processes

A Mac used lightly for web browsing and email by a single careful user sits in a very different risk category than a machine used by multiple people, running downloaded software from various sources, on an older OS version. The same check-list applies to both — but what it reveals, and how to act on it, depends entirely on that individual picture. 🧩