Avoid downloading dubious software from the apl-def.com scam website
Mac VirusAlso Known As: apl-def.com pop-up
Get free scan and check if your device is infected.
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What is apl-def[.]com?
apl-def[.]com is a deceptive website running several different scam variants. By claiming that the visitors' devices are infected, or that their internet connection is not secure, it attempts to trick them into downloading/installing nonoperational, untrusted or malicious software.
Few users access websites such as apl-def[.]com intentionally - they are usually redirected by intrusive advertisements or Potentially Unwanted Applications (PUAs) already infiltrated into the device.
![apl-def[.]com scam](/images/stories/screenshots202002/apl-def-com-scam-main.jpg)
The scams promoted by apl-def[.]com target iPhone users, however, this web page might be accessed (or visitors are redirected to it) via other Apple products as well. One variant of this scheme operates by claiming that three viruses have been detected on the user's device.
These fake threats have apparently already damaged the smartphone's battery. To prevent further damage, the scam instructs users to download/install the recommended free virus protection tool from the AppStore. This software will remove the nonexistent malware and repair the damage, which the device has supposedly suffered.
Another version, states that the internet connection may not be secure. As with the previously described variant, this scam promotes a dubious app (a "trusted VPN"), which will allegedly secure the connection. It also repeats identical download/install steps. Note that all information provided and claims made by schemes run on apl-def[.]com are false.
Furthermore, trusting these scams will allow dubious or potentially malicious content onto the device. Therefore, you are strongly advised against trusting apl-def[.]com or other similar web pages.
As well as force-opening deceptive/scam sites, PUAs can cause redirects to sale-oriented, untrusted, rogue, compromised and malicious web pages, however, unwanted applications might also have other/additional capabilities. They can run intrusive ad campaigns, which deliver dangerous ads that diminish the browsing experience.
Once clicked, these redirect to various harmful websites and can even stealthily download/install unwanted software. Other PUAs can modify browsers and limit/deny access to their settings. PUAs commonly have data tracking capabilities.
They can monitor browsing activity (URLs visited, pages viewed, search queries typed, etc.) and collect users' personal information (IP addresses, geolocations and other sensitive details). The gathered data is often shared with third parties seeking to misuse it for profit - potentially, by putting it to criminal use.
In summary, the presence of PUAs on systems can lead to various infiltration and infections, serious privacy issues, financial loss and even identity theft. To protect device integrity and user safety, remove all suspect applications and browser extensions/plug-ins without delay.
| Name | apl-def.com pop-up |
| Threat Type | Phishing, Scam, Mac malware, Mac virus. |
| Fake Claim | It claims that the visitors' devices are infected or that their internet connection may not be secure. |
| Detection Names | Fortinet (Phishing), Full List (VirusTotal) |
| Serving IP Address | 5.9.122.84 |
| Promoted Unwanted Application | Scam promotes various untrustworthy applications. |
| Symptoms | Your Mac becomes slower than normal, you see unwanted pop-up ads, you are redirected to dubious websites. |
| Distribution methods | Deceptive pop-up ads, free software installers (bundling), fake Flash Player installers, torrent file downloads. |
| Damage | Internet browser tracking (potential privacy issues), display of unwanted ads, redirects to dubious websites, loss of private information. |
| Malware Removal (Windows) |
To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Combo Cleaner. Download Combo CleanerTo use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by RCS LT, the parent company of PCRisk.com. |
safariosso-aplosso.com, vpnshieldplus4.com, and maztek.xyz are some examples of other scam web pages similar to apl-def[.]com. These schemes use social engineering and scare tactics to trick visitors into performing specific actions.
For example, users can be encouraged to download/install or purchase nonfunctional, untrusted or malicious content, calling fake and expensive technical support lines, making monetary transactions (e.g. fraudulent fees and other payments), revealing personal information (e.g. names and surnames, social networking/media account credentials, banking or credit card details), and so on.
Deceptive sites are quite common, and therefore you are advised to exercise caution when browsing.
How did potentially unwanted applications install on my computer?
PUAs can be downloaded/installed with other products. This deceptive marketing method of pre-packing software with unwanted or malicious additions is called "bundling". Rushing download/installation processes (e.g. ignoring terms, skipping steps and sections, etc.) increases the risk of inadvertently allowing bundled content onto the system.
Some PUAs have "official" download pages. When clicked, intrusive ads can execute scripts to download/install PUAs without users' permission.
How to avoid installation of potentially unwanted applications
Products should be researched to verify their legitimacy, before download/installation or purchase. Use only official and trustworthy download channels. Unofficial and free file-hosting websites, P2P sharing networks (BitTorrent, eMule, Gnutella, etc.) and other third party downloaders are untrusted and can offer likewise suspect content.
Treat download and installation processes with caution.
Read the terms, explore all available options, use the "Custom/Advanced" settings and decline offers to download/install additional apps, tools, features, etc. Intrusive ads typically seem normal and harmless, however, they can redirect to dubious web pages (e.g. pornography, adult-dating, gambling and others).
If you encounter these advertisements/redirects, inspect the system and immediately eliminate all suspicious applications and browser extensions/plug-ins. If your computer is already infected with PUAs, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate them.
Text presented in the apl-def[.]com scam:
Apple Security
(3) Viruses has been detected on your iPhone and battery has been infected and damaged.
If you do not remove this malware now, it may cause more damage to your device.
How to fix this:Step 1: Tap the button below & install the recommended virus protection tool for free from the AppStore.
Step 2: Run the app to remove all malware to repair your phone to 100%
Download and Install
Screenshot of another scam variant promoted by apl-def[.]com site:
![apl-def[.]com scam alternative variant](/images/stories/screenshots202002/apl-def-com-scam-alternative-variant.jpg)
Text presented in this variant:
Your Internet Connection Maybe is Not Secure!
Install a Trusted VPN From the Appstore For Free and Protect Your Internet Connection!
How to Protect Your Connection:
Step 1. Click on the Button “Download” Below and Install the Recommended Application from the Appstore (Free)
Step 2. Open the Installed Application and Protect Your Internet Connection
DOWNLOAD
To enable pop-up blocking, fraudulent website warnings, and remove web browsing data in mobile Apple devices, follow these steps:
First, go to "Settings", and then scroll down to find and tap "Safari".

Check if the "Block Pop-ups" and "Fraudulent Website Warning" toggles are enabled. If not, enable them immediately. Then, scroll down and tap "Advanced".

Tap "Website Data" and then "Remove All Website Data".

Instant automatic malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
DOWNLOAD Combo CleanerBy downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by RCS LT, the parent company of PCRisk.com.
Quick menu:
- What is "apl-def[.]com"?
- STEP 1. Remove PUA related files and folders from OSX.
- STEP 2. Remove rogue extensions from Safari.
- STEP 3. Remove rogue add-ons from Google Chrome.
- STEP 4. Remove potentially unwanted plug-ins from Mozilla Firefox.
Video showing how to remove adware and browser hijackers from a Mac computer:
Potentially unwanted applications removal:
Remove potentially unwanted applications from your "Applications" folder:

Click the Finder icon. In the Finder window, select "Applications". In the applications folder, look for "MPlayerX","NicePlayer", or other suspicious applications and drag them to the Trash. After removing the potentially unwanted application(s) that cause online ads, scan your Mac for any remaining unwanted components.
DOWNLOAD remover for malware infections
Combo Cleaner checks if your computer is infected with malware. To use full-featured product, you have to purchase a license for Combo Cleaner. 7 days free trial available. Combo Cleaner is owned and operated by RCS LT, the parent company of PCRisk.com.
Mac malware removal and recovery procedure
Common Mac malware behaviors
VisibleAdware injection - browser hijackers and fake search engines
The most common Mac malware. Replaces your default search engine, homepage, or new-tab page with a lookalike domain that funnels every query through ad networks before passing it to a real provider. Often arrives bundled with cracked apps, fake Flash Player updates, or "free media player" downloads (MPlayerX, NicePlayer).

HiddenLaunchAgent / LaunchDaemon persistence
The standard way Mac malware survives reboots. A small .plist file in /Library/LaunchAgents/, /Library/LaunchDaemons/, or ~/Library/LaunchAgents/ tells launchd to run the malware at every login or boot. The .plist often picks a generic-looking name like com.apple.AdobeFlash.plist or com.system.helper.plist to blend in among legitimate Apple files.

HiddenConfiguration Profile abuse
Configuration Profiles are an enterprise feature - they let an IT department enforce policy on managed Macs (homepage, DNS, certificates, password rules). Adware abuses this by silently installing a Profile that locks the browser homepage, default search, or DNS server at the OS level. Manual browser reset doesn't help - the Profile reapplies the hijack. Check System Settings → General → Device Management (or "Profiles" on older macOS).

VisibleFake update prompts (FlashPlayer.dmg variants)
"Your Flash Player is out of date" or "Update your browser to view this content." Adobe killed Flash in 2020 - any current "Flash update" prompt is malware. The Atomic macOS Stealer (AMOS) family heavily uses this trick to deliver info-stealers that grab browser passwords, keychain items, and crypto wallet seed phrases. Apple's Software Update never appears as a browser pop-up.

SymptomCryptominer CPU usage
Fans spin loudly, the Mac runs hot, battery drains fast, Activity Monitor shows a process near 100% CPU. Cryptominers run silently in the background to mint cryptocurrency for the attacker. Often delivered via cracked apps from torrent sites, browser extensions, or supply-chain compromises in legitimate Mac software.

HiddenInfo stealing - AMOS, Banshee, Cthulhu, RustDoor
Modern Mac stealer families - AMOS (Atomic macOS Stealer), Banshee, Cthulhu, and RustDoor are the most active - read browser-saved passwords, cookies, autofill data, the macOS Keychain, crypto wallet seed phrases (Exodus, Electrum, Trezor Suite, MetaMask, etc.), and Apple Notes. AMOS is the most prolific overall, distributed via fake software installers, cracked apps, and fake "Spotlight" or "ChatGPT" sites. Once data is exfiltrated, the malware often deletes itself, leaving little trace - which is why credential rotation in Step 10 is critical even after the infection appears gone.
Click the Wi-Fi icon in the menu bar (or open Control Center) and turn Wi-Fi off. If you're on Ethernet, unplug the cable. This stops any active info-stealer or backdoor from sending data out or accepting commands. Keep the network off until you've booted into Safe Mode (next step) - you'll reconnect there briefly to download the scanner.
macOS Safe Mode loads only Apple-trusted kernel extensions and skips most third-party LaunchAgents and user login items, so persistent Mac malware doesn't auto-run while you set up the scanner. Network access works normally in Safe Mode.
- Choose
- Wait until the Mac is fully off
- Press and hold the Power button until "Loading startup options" appears
- Select your startup disk (usually "Macintosh HD")
- Hold Shift, then click Continue in Safe Mode
- Log in - the menu bar will show "Safe Boot" in red
Intel-based Mac
- Choose
- Immediately press and hold the Shift key as the Mac begins to boot
- Release Shift when the login window appears
- Log in - the menu bar will show "Safe Boot" in red
Once Safe Mode has loaded, turn Wi-Fi back on and download Combo Cleaner for Mac. Save the .dmg to your Desktop. You can disconnect Wi-Fi again before scanning if you want extra caution.
Open Activity Monitor (, or Cmd+Space and type "Activity Monitor"). Sort by CPU usage to spot cryptominers and runaway processes.
Click each unfamiliar process and choose (Cmd+I) to see:
- Path - anything in
/private/tmp/,~/Library/Application Support/<random-name>/, or with a generic-looking bundle ID is suspicious - Code signing - Apple's processes are signed by "Apple" or "Software Signing." Adhoc-signed or unsigned binaries from third parties warrant investigation
- Open Files and Ports - shows what the process is touching on disk and network

Download KnockKnock by Objective-See (Patrick Wardle's free tool, the Mac equivalent of Sysinternals Autoruns). It lists every place macOS malware can persist in a single window: LaunchAgents, LaunchDaemons, Login Items, Cron Jobs, Browser Extensions, Kernel Extensions, Authorization Plug-ins, Mail Plug-ins, Quicklook, Spotlight, and more.
Run KnockKnock and toggle "Filter Signed Items" to focus on unsigned or non-Apple-signed entries. Click any suspicious item to see its file path and code-signing status.
If you'd rather check manually, open Finder → (Shift+Cmd+G) and visit each path:
/Library/LaunchAgents/- system-wide, runs at login for any user/Library/LaunchDaemons/- system-wide, runs at boot before login~/Library/LaunchAgents/- user-level, runs at this user's login~/Library/Application Support/- where adware drops its data folder, often with a random or app-mimicking name
Then check additional persistence locations in System Settings:
- Login Items & Extensions - . Click anything you don't recognize and remove it
- Background Items - same panel, "Allow in the Background" section. Mac malware often shows up as a background item with an obscure name
- Configuration Profiles - (or "Profiles" on older macOS). Remove any Profile you didn't install yourself
<key>Program</key> and <key>ProgramArguments</key> values tell you exactly what executable runs and from where. Don't delete yet - write down the file paths and entry names. We'll remove them after the Combo Cleaner scan in Step 7.
Mac malware sometimes redirects bank, Apple, antivirus, and update domains to attacker-controlled servers via the hosts file or DNS settings.
Hosts file: Open Terminal () and run:
sudo nano /etc/hosts
Legitimate entries are commented with #. Any uncommented IP-to-domain mapping is suspicious - especially redirects for apple.com, icloud.com, your bank, or your password manager. Press Ctrl+X to exit nano without saving.
DNS settings: → click your active connection (Wi-Fi or Ethernet) → Details → DNS. Confirm DNS servers point to your ISP, your router, or a known public resolver (Cloudflare 1.1.1.1, Google 8.8.8.8). Anything else has been hijacked.
chase.com and you'll be at the attacker's clone.Open the .dmg you downloaded in Step 2. Drag the Combo Cleaner icon to the Applications folder. Open it from Launchpad (or Applications), allow it to update its threat database, then click Start Combo Scan and let it complete fully. Review what it found and apply the recommended actions.

Reopen KnockKnock (or revisit the Finder paths from Step 4). Anything you flagged that's still present hasn't been caught by the automated scan. For each remaining suspicious entry:
- Note the executable path the .plist references (right-click the .plist → Open With → TextEdit, look at
<key>Program</key>) - Move the .plist to Trash
- Move the executable file at the referenced path to Trash
- Empty the Trash
Then go to /Applications and remove any unwanted apps the malware installed. Common adware-installed app names: MPlayerX, NicePlayer, MyShopcoupon, Advanced Mac Cleaner, Mac Cleanup Pro. Drag them to Trash, then check ~/Library/Application Support/ for any folder with the same name and delete it too.
Mac adware persists in browser extensions, search engine settings, homepage, and notification permissions. Reset each browser you use:
- Safari: - uninstall anything you don't recognize. Then - restore your preferred default search engine. Then - remove all unfamiliar sites. For a deep reset: → "all history."
- Chrome: visit
chrome://settings/reset→ "Restore settings to their original defaults." Thenchrome://settings/content/notificationsand remove unfamiliar sites. - Firefox: open
about:support→ Refresh Firefox. Then check .
Review installed extensions in each browser and remove anything you don't recognize, especially extensions you didn't install yourself.
Some Mac malware tries to weaken built-in security to make persistence easier. Verify each is on:
- Gatekeeper (blocks unsigned apps): → scroll to Allow applications downloaded from → confirm "App Store and identified developers" is selected (not "Anywhere"). If the malware added itself to the allow-list, the entry appears in the same panel - remove it.
- FileVault (full-disk encryption): → confirm "FileVault is on for this disk." If it was disabled by malware, turn it back on.
- System Integrity Protection (SIP): open Terminal and run
csrutil status. Output should be "System Integrity Protection status: enabled." If disabled, you'll need to reboot into Recovery Mode and runcsrutil enablefrom there.
Then run macOS Software Update () to apply the latest security patches.
If the malware was an info-stealer (AMOS, Banshee, Cthulhu, or RustDoor families are extremely common on Mac), assume every password saved in your browser is compromised. So is your iCloud Keychain if it was unlocked while the malware ran. Change passwords from a different, known-clean device - your iPhone is fine if it's not infected.
Recommended order:
- Apple ID first - it controls iCloud, Find My, Apple Pay, and the App Store
- Primary email - the recovery hub for everything else
- Banking and financial accounts
- Password manager master password (if you use one)
- Crypto wallet seed phrases - if you store any seed phrase or private key on the Mac, AMOS specifically targets these. Move funds to a fresh wallet from a clean device immediately, before changing other passwords
- Social media, shopping, and remaining accounts
Where available, enable phishing-resistant multi-factor authentication (passkeys / hardware keys / authenticator apps) - SMS-based MFA is bypassable.
Reconnect to the network and run one final full scan with Combo Cleaner. Open and confirm nothing suspicious has reappeared. Open Activity Monitor and verify no unfamiliar process is using significant CPU.
Over the next 7 days, watch for symptom recurrence: high CPU when the Mac is idle, browser redirects returning, fake update prompts, or unfamiliar Login Items reappearing. If anything returns, you missed a persistence point and the procedure needs to be repeated - or you may have a deeper compromise that requires a clean macOS reinstall.

When to reinstall macOS instead
Manual removal isn't always the right answer. Reinstalling macOS from scratch is the only way to be 100% certain when:
- The malware reappears after every removal attempt
- A kernel extension or system-level component was modified
- Confirmed credential-theft malware ran with admin rights - the system likely has multiple unknown payloads
- The Mac is used for online banking, crypto wallets, business email, or anything where partial doubt isn't acceptable
macOS reinstall is straightforward: shut down → boot to Recovery (Apple Silicon: hold the Power button → Options; Intel: Cmd+R during boot) → Erase Mac → Reinstall macOS. Back up documents to external storage first, scan the backup with Combo Cleaner before restoring it, and reinstall apps fresh - never restore them from a backup of the infected system.
Important: Manual removal of Mac malware requires care - deleting the wrong .plist or system app can prevent macOS from booting normally. If you're not confident identifying system files from malicious files, run an automated scan with Combo Cleaner for Mac and stop there - that path catches the vast majority of consumer Mac malware without the risk of breaking macOS.
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Tomas Meskauskas
Expert security researcher, professional malware analyst
I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for pcrisk.com since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats.
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