authentik/website/docs/providers/proxy.md

---
title: Proxy Provider
---

:::info
This provider is to be used in conjunction with [Outposts](../outposts/outposts.md)
:::

This provider protects applications, which have no built-in support for OAuth2 or SAML. This is done by running a lightweight Reverse Proxy in front of the application, which authenticates the requests.

authentik Proxy is based on [oauth2_proxy](https://github.com/oauth2-proxy/oauth2-proxy), but has been integrated more tightly with authentik.

The Proxy these extra headers to the application:

| Header Name                    | Value                                               |
| ------------------------------ | --------------------------------------------------- |
| X-Forwarded-User               | The user's unique identifier (**not the username**) |
| X-Forwarded-Email              | The user's email address                            |
| X-Forwarded-Preferred-Username | The user's username                                 |
| X-Auth-Username                | The user's username                                 |

Additionally, you can add more custom headers using `additionalHeaders` in the User or Group Properties, for example

```yaml
additionalHeaders:
    X-additional-header: bar
```