[Bug]: SAML POST Binding to SAML SP /saml/acs endpoint with prefetching GET call

[stebenz]

Preflight Checklist

• I could not find a solution in the documentation, the existing issues or discussions
• I have joined the ZITADEL chat

Version

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Describe the problem caused by this bug

A SAML SP application, which you get redirected to after a successful or failed login, expects a FormPost or Redirect with specific data. Here for the FormPost, nextJS does a prefetch for some reason, which results in a Forbidden answer from the application. This occurs because it's a GET call without any data/parameter which would be expected.

To reproduce

Steps to reproduce:

1. add project and application to Zitadel
2. try to login through POST-Binding response
3. "Forbidden" in application

Screenshots

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Expected behavior

There should not be a GET call before the expected FormPost.

Relevant Configuration

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Additional Context

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