The popularity of USB devices and external drives It has boosted our productivity, mobility, and ease of file transfer… but it has also opened up a serious risk front for businesses and professionals. USB flash drives, hard drives, and portable accessories, no matter how small they may seem, are behind a huge number of security incidents and information leaks that cost companies millions. If you work with sensitive data, blocking or controlling the USB ports on your Mac is no longer a whim: it's a essential safety measure.
In addition, macOS is fully integrated into the corporate environment: iMac, Mac mini, MacBook and company coexist in corporate and mixed networks, so preventing anyone from copying classified information to a USB or connecting malicious accessories is key. In this guide, I explain in great detail: How to block USB ports on Mac, what methods are available to you, and how it all fits with MDM policies, encryption, and even certified sustainability criteria.
Why you might want to block USB ports on your Mac
If you manage critical data or shared equipment, it makes sense to consider blocking or restricting ports. In short, we're talking about reduce attack surface, maintain confidentiality and prevent malware from entering where you least expect it.
To begin with, the leak prevention It is essential. Limiting USB usage makes it difficult for someone to copy files to a flash drive or external drive without permission and protects the intellectual property and trade secrets. This control is especially useful in environments with users with different access profiles.
Another point in favor is the defense against the malware that spreads via USB. There are threats that arrive camouflaged in seemingly harmless memory and, once connected, can compromise the system or plant backdoors. Blocking or requiring authorization minimizes this risk and reinforces the safety hygiene.
It is also a key decision in physical security. In offices, classrooms, stores, or spaces where the Mac isn't always monitored, restricting the use of USB ports prevents anyone from connecting uncontrolled devices. If you find what you're reading useful, don't hesitate to share it with us. share it with your team: Safety is everyone's business.
Quick Option: Physical Locks for USB Ports
If you don't want any configuration hassles and just need something immediate, the physical port blockers They're your ally. They're small "plugs" that plug into your USB port (or even Thunderbolt with the appropriate adapter) and prevent anything from connecting without the appropriate dongle.
Advantages: they are simple, they do not impact the system and their installation is easy. two minutes. Disadvantages: They don't differentiate between users or devices, and if you lose the key, you have to buy a replacement. However, for exposed equipment or public areas, they work wonderfully. first level barrier.
Software USB Blocker: Fine-grained control with iBoysoft DiskGeeker
When you need granularity (allowing some USBs and blocking the rest), a software blocker for macOS speeds things up. One popular option is iBoysoft DiskGeeker, a suite of disk utilities for Mac that, in addition to optimizing and repairing, includes the function USB Defender to manage what connects and what doesn't.
The idea is simple: you establish a password and a White list of devices. If a USB or Thunderbolt accessory isn't authorized, your Mac won't mount or recognize it. This means your devices only communicate with what you've previously approved, which provides a perfect balance between safety and comfort.
How to activate it in general terms: first you install the app, enter the menu (three dots icon), choose USB Defender and enable protection. Then you define a password (short and strong) and choose the mode: allow only those on the white list or ask for confirmation every time something to be connected. The result is a controlled access system that's easy to reverse when you need to.
Practical tip: Use a whitelist for your work drives and require a password for the rest. This way, your daily routine remains as simple as ever. agile, but you block what it doesn't touch as soon as an unknown device appears.
Disable kexts to block USB on macOS 10.15 or earlier
On older macOS (up to macOS 10.15 Catalina) it's possible to cut corners by disabling the kernel extensions (kexts) that manage USB storage. Note: This is a technical method and cannot be reversed without repeating steps, but it leaves the ports completely "inert" for removable media.
The logic is that if the system doesn't load the corresponding kexts, the Mac loses the ability to interact with external drives. It's an all-or-nothing approach: very useful for blocked teams or with very strict compliance needs, and less appropriate if you need to connect accessories frequently.
Before touching anything, remember that from macOS 11 BigSur Apple introduced the Signed and Sealed System Volume (SSV), which prevents tampering with system files. Therefore, this method only applies to earlier versions (up to 10.15). In Big Sur and later, you must choose other methods, as described below.
As a guide, the steps include temporarily disabling the System Integrity Protection (SIP), access the system extensions folder and move out the kexts that manage USB. Specifically, the common ones in this scenario are IOUSBMassStorageClass.kext y IOFireWireSerialBusProtocolTransport.kextAfter a reboot, the USB ports stop accepting external storage; if you want to go back, return the kexts to their original location and reboot.
An interesting nuance: if you only remove the mass storage part (IOUSBMassStorageClass.kext), you can keep certain peripherals operational while blocking only the units. Still, test it in a test environment before implementing it in production.
USB Restricted Mode: Accessory Security on macOS 13 or later
On Macs with Apple Silicon and modern versions of the system, Apple strengthens protection with the Accessory Safety (the famous "restricted mode"). Starting with macOS 13 Ventura, the system asks for your permission when connecting new accessories by cable when the device is locked, and you can require verification each time.
The beauty of this additional layer is that it prevents unauthorized connection attempts and requires explicit trust. If you enable the always askNo data transfer takes place until you confirm. Perfect for teams that pass through many hands or for those who are very careful about their attack surface.
To configure it, you go to the Apple menu, go to System Settings, section Privacy & Security, you slide to "Allow accessories to be connected" and select the option for permanent consultation. The change requires entering the administrator password To confirm.
Take advantage and also check out the section of Users and groups to confirm that there are no accounts with unnecessary interactive access. If you use the "Guest" account, disable it or limit it as much as possible. And a classic but effective reminder: lock your Mac when you're away; Restricted Mode really shines when the session is blocked up.
Centralized management with Microsoft Intune (MDM)
If you manage a fleet of equipment, the ideal is to orchestrate everything from an MDM platform. Microsoft Intune It is part of Microsoft's Enterprise Mobility + Security suite and allows you to apply corporate policies to macOS, iOS, Android, and Windows from a central console.
With Intune you can strengthen the Mac ecosystem by requiring FileVault, managing extension permissions, enforcing security standards, and controlling who connects accessories and how. On macOS, the combination of Accessory Security, privacy policies, and encryption gives you comprehensive control over device without losing traceability.
And a style note that many administrators repeat with humor: it is written Intune, no «InTune»Joking aside, integrating MDM into your company's workflow makes the difference between improvising and truly govern the fleet.
Encryption: FileVault and password-protected external drives
Blocking USB ports is a layer, but the encryption is another equally important one. On a Mac, you can activate FileVault to encrypt the internal disk: this way, even if someone has the computer in their hands, they will not be able to access the data without your consent. password. It's enabled in your Privacy & Security settings and doesn't delete existing content.
For external devices (pendrives and disks), when formatting them with Disk Utility you can encrypt a usb stick and password-protect them. Every time you plug that USB into a Mac, the system will ask for the password before mounting the volume. In many scenarios, you can encrypt without erasing if you use APFS and convert the volume to encryption directly.
One thing to keep in mind: if you encrypt an external drive, you won't be able to connect it to a AirPort base station to use it as a Time Machine destination. This isn't a bug, it's a system limitation that you should plan for so you don't miss out on automated backups.
Where do I start? Open Disk Utility, select the external volume, choose options, and then click OK. encryption and set a strong password. For the internal drive, enable FileVault from the system settings. It's a simple gesture that multiplies the resilience of your data against loss and theft.
Sustainability criteria: GRS certification and recycled material
If you are going to purchase physical blockers or port accessories, you may want them to meet standards of sustainabilitySome products claim to contain at least one 50% recycled material and are certified by independent bodies throughout the entire supply chain.
The certification Global Recycled Standard (GRS) Ensures that recycled content is verified at every stage, from source to final product, and that social, environmental, and chemical requirements are met. This type of certification also supports initiatives such as Climate Pledge Friendly, which promote responsible purchasing.
For reference, there are products certified by Bureau Veritas with certification number TE-00318854. Verifying this data helps you buy wisely and align physical security with policies responsibility environmental impact of your company.
Good practices and quick recommendations
Beyond technique, there are habits that make the difference. Keep your Mac updated, applies the principle of least privilege, logs who connects to what, and, where feasible, combines port blocking with encryption and MDM policies. This mix is what really it works long term.
If you manage shared equipment, consider a mixed approach: physical locks on exposed workstations, USB Defender with White list In production and accessory safety equipment, it's configured to always ask questions. It's a "belt and suspenders" that prevents scares and doesn't slow down daily work.
FAQs
- What is the easiest way to block USB on a Mac?
-
If you are looking for immediacy, the physical blockers Ports are the quickest: just plug them in and go. If you prefer granular control without touching the hardware, a utility like USB Defender in iBoysoft DiskGeeker lets you authorize by White list and ask for a password.
- I'm using macOS 13 or later, can I disable kexts?
-
No. Since macOS 11 BigSur, the system volume is signed and sealed and does not allow modifications of this type. In modern versions, it relies on Accessory Security and on security solutions. management with MDM.
- Can I allow some USBs and block all others?
-
Yes. With a software blocker that supports white lists, you authorize your trusted devices and the rest are excluded. In addition, you can require password for each connection if you prefer.
- Does encryption replace port blocking?
-
Noel encryption Protects content, but does not prevent devices from being connected or malware from being injected via USB. Ideally, a combination of both: blocking or restricting ports and encrypting internal and external disks. External.
- What role does Microsoft Intune play on Mac?
-
Intune, part of Enterprise Mobility + Security, centralizes security policies on macOS: FileVault, permissions, privacy standards, and health monitoring. Helps keep your Macs compliant and under control. control.
- What is the GRS certification you mention?
-
GRS (Global Recycled Standard) verifies content recycling and responsible practices throughout the supply chain. Some security accessories carry certifications such as those issued by Bureau Veritas (e.g., TE-00318854), which adds transparency and trust.
You have a full range of measures to protect your Macs: from physical blockers From native features like Accessory Security to specialized whitelisting software, plus support for encryption and MDM platforms like Intune—choose the combination that fits your environment, budget, and security culture, and get it up and running without any issues.
