WPS and why you turn it off

In short: WPS (“Wi-Fi Protected Setup”) was meant to make joining Wi-Fi easier by button press or PIN, but the PIN variant is insecure.

In more detail: The eight-digit PIN is checked by the router in two halves. As a result at most about 11,000 attempts suffice instead of 100 million. Attackers within radio range can recover the PIN, and with it the Wi-Fi password, within hours.

In Depth

• Variants: Push button, router PIN, device PIN, NFC.
• Weakness: The last digit is a checksum, and the first and second halves are confirmed separately. Tools such as Reaver exploit this.
• Vendor counter-measures: Lockout times after failed attempts, which do not work everywhere.
• Recommendation: Turn off PIN WPS in the router. The button variant is open only briefly and much less problematic.
• Better: A long WPA3 or WPA2 password and a QR code for guests. See Wi-Fi security.
• Guest network: Set up a separate network for visitors.

See also: RADIUS