X-Forwarded-Host can contain multiple hosts #6215

Is there an existing issue for this?

• I have searched the existing issues

OS/Web Information

N/A

Steps to Reproduce

X-Forwarded-Host: <host>, <host>

Expected

We need to split this header and use the first.

Edit: actually unclear to me whether this is valid syntax for the header. While it does seem unusual the header is non-standard so this seems fair enough.

Actual

We use the whole thing.

Logs

No response

Screenshot/Video

No response

Does this issue happen in VS Code or GitHub Codespaces?

• I cannot reproduce this in VS Code.
• I cannot reproduce this in GitHub Codespaces.

Are you accessing code-server over HTTPS?

• I am using HTTPS.

Notes

No response