I follow phpBB3 development and its development discussions.
This also included all security reports.

To this day, No phpBB3 board by itself with no modifications has ever been hacked.
Every report always traces to a server security issue, someones simple ( FTP, server or admin password), or some other modification, script or software that had a security issue.

An issue has never been found directly with phpBB3 itself.

phpbb is a opensource and have a great security. They are developing and em biding more and more security every day. I have used it and never had a complain.

Since hackers can see the logins, they already have one piece of the puzzle and forums say that weak passwords can be brute forced (I guess no consecutive login failure lock mechanism in phpBB3)

"mine was only 8 characters with only numbers and letters when mine got hacked so i increased the complexity. other forums like VBulletin and Invision Power have lock out features after invalid attempts which help keep out the hackers. Plus within Invision your login ID can be different from your display handle. "

Also, as you install modules, re-check your security profile.

Your not correct, phpBB3 has always had a failure block for failed passwords.
3 times and it locks it and forces captcha which can also be extended.

I don't need to check anything. As I said I have been involved with phpBB3 since day one and every investigation turns up not being a security issue in phpBB3.

I have numerous high traffic phpBB3 sites and none of them have ever been hacked.
One of them has a couple hundred users online at any given time and has been there since phpBB3 RC's, before the official release. Not to mention the official phpBB.com forum which has even more traffic.

phpBB3 has a full security settings page in the admin. Have you ever looked at the settings?
Force Password Change
Max number of login tries
Password complexity
IP validation, etc......
Password Length

You again prove it here. You had a week password. That is not phpBB3's fault, its your own as it would be in any software.

I would like to see a phpBB3 forum hacked, without any other openings, through the actual core software itself.
With a password that I would typically use IM5BnS2cW0lnSuiD401H