The Push API is a web standard that lets a browser receive messages for a site even when the page is closed. It works with a push service and a subscribed user permission, so a website can trigger a notification or update later without keeping a live connection open.
In cyber security, that convenience can become a delivery channel for abuse. Legitimate services use it for alerts, reminders, and security prompts, but attackers can exploit the same permission to send scam notifications, fake warnings, and phishing links that appear trustworthy because they come through the browser. Defenders watch for deceptive permission prompts, revoke abusive subscriptions, and apply rate limits or reputation checks to reduce spam. The key security lesson is that the Push API itself is not malicious; the risk comes from how sites request and use the subscription.