$.ajax calls the success callback in FF 3.5.8 for failed cross-origin requests.

[jambo]

In Firefox 3.5.8, when I attempt an illegal cross-origin request, the "success" callback is still called. Firefox's response to an illegal cross-origin request is now to blank xhr.responseText and set xhr.status to zero, even though xhr.readyState === 4.

This should be reproducable by simply attempting a cross-origin request to a domain that does not support it, for example with the following code:

$.ajax({

url : " http://www.example.com/", success : function() {

alert( "Oops!" );

}

});

[maqdev]

The same with: Google Chrome 5, Safari 4.0.4 (Win)

Also this problem is reproduced not only for cross-origin request, but when server is down and closes connection without any HTTP status response (in last case reproduced with IE8 too).

[maqdev]

Here is similar problem and a fix that could help:

 http://dev.jquery.com/ticket/6060

[curiousdannii]

Can be closed as #6060 has been fixed.

[addyosmani]

Closing as we've fixed this.