I just had an item missed and the status says "Extra confirmation (weak password?)". I've had snipes over the pass few days work fine and the password is sufficiently secure.
When you see "Extra confirmation" error, that means that eBay did not provide any errors at all so I can only suspect what was really wrong.
That usually happens for one of the following reasons:
1. Bad password (your password has some dictionary words, numbers only or part of your user id).
If your password worked fine in the past, it does not mean it's strong. eBay changes and improving password system constantly so your yesterday's good password may be too weak today:
http://www.myibay.com/forums/viewtopic/1316/short-or-weak-password-will-prevent-you-from-bidding/ Fix: Changing a password to something more longer and secure will help (adding a few more digits is usually enough).
2. Something is wrong with your eBay account.
Fix: Please check your "My Messages" on eBay to see if you have some warnings like expired Credit Card, some payment dues (if you sold something in the past), etc.
3. eBay was overloaded during its peak hours.
Fix: unfortunately, there is nothing you can do about it. But on my own experience, eBay is getting much better on peak hours compared to what was happening about a year or so ago.
Those small peak hours outages happens very rare, but it happens.