<p></p>
<p><b>@AntonKhorev</b> commented on this pull request.</p>

<hr>

<p>In <a href="https://github.com/openstreetmap/openstreetmap-website/pull/4455#discussion_r1573845454">app/controllers/users_controller.rb</a>:</p>
<pre style='color:#555'>> @@ -101,14 +107,9 @@ def create
       if current_user.invalid?
         # Something is wrong with a new user, so rerender the form
         render :action => "new"
-      elsif current_user.auth_provider.present?
-        # Verify external authenticator before moving on
-        session[:new_user] = current_user.slice("email", "display_name", "pass_crypt", "pass_crypt_confirmation")
</pre>
<p dir="auto"><code class="notranslate">session[:new_user]</code> filtered out other parameters such as <code class="notranslate">auth_provider</code> which was added later in <code class="notranslate">auth_success</code>. A new users was created from <code class="notranslate">session[:new_user]</code>.</p>
<p dir="auto">With <code class="notranslate">session[:new_user]</code> gone its possible to create users with fake values for <code class="notranslate">auth_provider</code> by opening the signup form like this: <code class="notranslate">/user/new?auth_provider=test1&auth_uid=test1</code></p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br />Reply to this email directly, <a href="https://github.com/openstreetmap/openstreetmap-website/pull/4455#pullrequestreview-2013475241">view it on GitHub</a>, or <a href="https://github.com/notifications/unsubscribe-auth/AAK2OLKZTMYK7BQB4JRDBODY6PSKVAVCNFSM6AAAAABBLOL2OWVHI2DSMVQWIX3LMV43YUDVNRWFEZLROVSXG5CSMV3GSZLXHMZDAMJTGQ3TKMRUGE">unsubscribe</a>.<br />You are receiving this because you are subscribed to this thread.<img src="https://github.com/notifications/beacon/AAK2OLLLILXE4WE3ZNSOQQ3Y6PSKVA5CNFSM6AAAAABBLOL2OWWGG33NNVSW45C7OR4XAZNRKB2WY3CSMVYXKZLTORJGK5TJMV32UY3PNVWWK3TUL5UWJTTYAMY2S.gif" height="1" width="1" alt="" /><span style="color: transparent; font-size: 0; display: none; visibility: hidden; overflow: hidden; opacity: 0; width: 0; height: 0; max-width: 0; max-height: 0; mso-hide: all">Message ID: <span><openstreetmap/openstreetmap-website/pull/4455/review/2013475241</span><span>@</span><span>github</span><span>.</span><span>com></span></span></p>
<script type="application/ld+json">[
{
"@context": "http://schema.org",
"@type": "EmailMessage",
"potentialAction": {
"@type": "ViewAction",
"target": "https://github.com/openstreetmap/openstreetmap-website/pull/4455#pullrequestreview-2013475241",
"url": "https://github.com/openstreetmap/openstreetmap-website/pull/4455#pullrequestreview-2013475241",
"name": "View Pull Request"
},
"description": "View this Pull Request on GitHub",
"publisher": {
"@type": "Organization",
"name": "GitHub",
"url": "https://github.com"
}
}
]</script>