At Your Service - Abusing the Service Workers Web API

The Service Workers API is a modern web API that grants web developers advanced capabilities, such as acting as a proxy server, intercepting network requests and improving offline experience as a background service.

In Akamai, we have unique visibility into the world wide web traffic. We have witnessed a dramatic increase in usage of legitimate service workers in our customers web applications in the past year. We believe this trend also applies to malicious service workers as well.

In this talk we will cover new and emerging web based attacks that (ab)use the Service Worker web API. We will cover and demonstrate the attack flow where a potential attacker can amplify and persist his foothold on the client and exfiltrate sensitive information by abusing the service worker API.

Along showcasing those kind of attacks, we will also discuss and explain how to find those attacks and methods to mitigate and prevent them.

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