My main man RBA seems to have the exploitation of the software pretty well covered, but keep in mind all security tests follow the same formula for a reason:
Recon -> Scanning (like ports, nessus, etc.) -> then exploitation
So you want to check not only the software, but your network architecture to see what all is open to the world because it doesnt matter how secure your websphere box is if the next IP address on the network has telnet open and full admin permissions. Maybe this is out of scope for what your looking for, but it's definitely worth keeping in mind if you want to be as secure as possible. If it's hosted on a VPS or GoDaddy or something though, your just going to have to trust your hosting provider to take care of that.
Welcome and stuff, good luck with your testing
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