How can I have Google Cloud Security Scanner log into my app?

[Joshua Fox via StackOverflow]

I ran Google Cloud Security Scanner against my Google App Engine app. I asked it to authenticate against a "Non-Google Account" -- in other words, user-name/password fields in my webapp. However, I get back the message "Could not sign in using the provided username and password" each time.

(I tried it several times, specifying different user-agents and credentials and against two variants of my login page; and of course confirming that the credentials work when typed in manually. I have the necessary Editor-level permissions on the Google Cloud project.)

What do I need to do to get the Scanner to authenticate?

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http://stackoverflow.com/questions/38533638/how-can-i-have-google-cloud-security-scanner-log-into-my-app

[Adam via StackOverflow]

Here's what the docs say about Non-Google account authentication:

Note that support for login forms is still in development, and may not work out-of-the-box with your system. If you have confirmed your test account is able to login manually, but not in Cloud Security Scanner, use the feedback option within the tools to request support.

One possible workaround is to create a simplified alternative login form for the purposes of using the scanner if it's unable to work with the current one.

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http://stackoverflow.com/questions/38533638/how-can-i-have-google-cloud-security-scanner-log-into-my-app/38557726#38557726

[Adam via StackOverflow]