QNetworkAccessManager::authenticationRequired problems with SSL

I tried to access a PHP file which is in a htaccess restricted area of a Webserver which use HTTPS. In my example I tried it with AuthType Basic

The authenticationRequired() signal is triggered every few seconds. In the connected slot I set the username and password of the restricted area on the QAuthenticator object.

The log from the server shows that the request (which is a normal GET request), I also tried POST request, is sent a multiply of 100 per second so ~= 200 requests per second until the server give up.

It seems that the problem only occurs in combination of ssl and a restricted area

There are no error, sslerror or finished signals emitted, but I see the traffic in Wireshark.
The problem occurs on Windows, Mac and iOS.

When I enter the url in the browser, then it is working without a problem.