Turn on the firewall and stealth mode — via Apple Support

Hidden settinglow riskNeeds adminmacOS 14 Sonoma and later

The macOS firewall blocks unwanted incoming connections, but it isn't always switched on. Stealth mode goes further and makes your Mac ignore pings and probes from other devices, so it's harder to find on public Wi-Fi.

Takes effect right away

How to do it

  1. Open System Settings > Network > Firewall and turn it on.
  2. Click Options and turn on Enable stealth mode.
  3. For the strictest setup on untrusted networks, also turn on Block all incoming connections. It blocks incoming connections to non-essential services and apps, including sharing services such as file or screen sharing.
With the normal firewall settings, services you've turned on in Sharing settings can still accept connections through it. Block all incoming connections is stricter: it also blocks those non-essential sharing services. For extra safety, turn off Sharing services you don't need.

Sources

Source reviewed
2026-11-02
Link checked
2026-11-02
Tested hands-on
Not by Oddbyte.Me

Oddbyte.Me hasn't tried this on every macOS version, so keep the undo handy.

firewallstealth modepublic wi-fipingsecurity

More in Security & Privacy

Turn on FileVault so a stolen Mac can't be read — via Apple Support

Hidden settingmedium riskAdmin

On Apple silicon and T2 Macs the disk is always encrypted, but without FileVault it isn't tied to your password. Turning FileVault on means nobody can get at your files without your login password or recovery key. On older Intel Macs without a T2 chip it's the only disk encryption.

Find which app is using your mic or camera — via Apple Support

Tricklow risk

A coloured dot next to the Control Center icon tells you something is recording: orange means the microphone is in use, green means a camera is in use, and purple means system audio is being recorded. Opening Control Center tells you which app it is, so you can catch anything listening or watching when it shouldn't be.