As you may have read, Yahoo reported this week that a 2013 hack had resulted in it losing data on around a billion (a thousand million) customer accounts. The stolen data included usernames and passwords. This means that, if you have an active Yahoo account, chances are that someone could potentially have had access to it for the past 3 years.

More worrying, it also means that hackers could also have had access to any other systems on which you use the same password as your Yahoo one.

So although it's been a long time since the Yahoo attack, it's still a good idea to take some sensible precautions as a result of it. If you have a Yahoo account that you still use, it's important to change your password. And if you used your Yahoo password for other systems too, or if you think you might have done, it's very important that you change those too.

Latest reports suggest that the stolen database of Yahoo credentials was sold to at least 3 separate buyers, so it's definitely worth changing your passwords now. Just in case those buyers have now started using them.  Read More