So it looks like Yahoo finally is trying to reclaim some of the millions of defunct email addresses which have likely been idly sitting on their servers collecting dust. While this means that they’ll be able to offer some great new email addresses for users signing up to their network, it would appear to present an incredibly bad security risk for users of Yahoo’s network.
This article goes into detail on whats going on. I recommend that you take a quick read and then alert your customer base that they need to secure their Yahoo email accounts if they have any. Don’t want their email addresses falling into the wrong hands!