Detection via the error page

There may be times where we find JBoss AS running on port 8080, but the home page is unavailable. In cases like this, a 404 error page can also disclose the JBoss AS header and version number for the JBoss application instance in use:

A 404 error page can be generated by opening any random non-existent link, which will give us an error, as we can see in the preceding screenshot.