Envoy Admin Exposure

What is the "Envoy Admin Exposure?"

The "Envoy Admin Exposure" module is designed to detect potential misconfigurations in the Envoy proxy server. Envoy is an open-source edge and service proxy that is commonly used in modern microservices architectures. This module focuses on identifying instances where the Envoy Admin interface is exposed, which can lead to unauthorized access and potential security vulnerabilities.

This module has a medium severity level, indicating that while it may not pose an immediate threat, it should still be addressed to ensure the security of the Envoy deployment.

This module was authored by DhiyaneshDk.

Impact

If the Envoy Admin interface is exposed, it can allow unauthorized individuals to gain access to sensitive administrative functionalities of the Envoy proxy server. This can potentially lead to unauthorized configuration changes, data leakage, or even complete compromise of the server.

How does the module work?

The "Envoy Admin Exposure" module works by sending HTTP requests to the target server and analyzing the responses based on specific matching conditions. It checks for the presence of the "<title>Envoy Admin</title>" tag in the HTML response, indicating the presence of the Envoy Admin interface.

Additionally, it verifies that the response has a status code of 200 (OK) and that the "Content-Type" header is set to "text/html". These conditions help ensure that the target server is indeed exposing the Envoy Admin interface.

Here is an example of an HTTP request that the module may send:

GET / HTTP/1.1
Host: example.com
User-Agent: Vidoc-Scanner

The module then evaluates the response based on the defined matching conditions and reports any instances where the Envoy Admin interface is exposed.

It is important to note that this module does not perform any active exploitation or attempt to compromise the target server. It solely focuses on identifying potential misconfigurations and vulnerabilities related to the Envoy Admin interface.

For more information about Envoy, you can refer to the official documentation at https://www.envoyproxy.io/docs/envoy/latest/.