Compass Security Blog

Offensive Defense

A Note on Pentesting Passkeys

Some months ago, I performed a web application penetration test on an application that used passkey for authentication. As part of the assessment, I also tested the passkey implementation and noticed some unusual behavior. During the debugging process, I created two short JavaScript helper functions that can be used to hook the browser APIs involved in passkey operations, allowing the passkey configuration to be inspected and manipulated. This gave me the ability to reliably perform some passkey tests and assess the configuration and implementation.

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bRPC-Web: A Burp Suite Extension for gRPC-Web

The gRPC framework, and by extension gRPC-Web, is based on a binary data serialization format. This poses a challenge for penetration testers when intercepting browser to server communication with tools such as Burp Suite.

This project was initially started after we unexpectedly encountered gRPC-Web during a penetration test a few years ago. It is important to have adequate tooling available when this technology appears. Today, we are releasing our Burp Suite extension bRPC-Web in the hope that it will prove useful to others during their assessments.

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Burp Extension: Copy Request & Response

Writing good reports is key in penetration tests / security assessments, since this is the final result delivered to the customer. Vulnerabilities should be described in a way so that the customer can understand and also reproduce the issue. For web application pentests, the best way is often to show the HTTP requests and responses to explain an issue. This Burp Suite extension “Copy Request & Response” can assist you while the report.

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New Security Enhancing HTTP Headers

In the past few years, several new HTTP Headers have been proposed to increase the security of web applications. This is being done by providing additional instructions and information about the served application to the browser. Those can mitigate and avert various common web attacks, even if the underlying application contains vulnerabilities, therefore adding another […]

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