Yahoo have confirmed that all 3 billion user accounts were affected in a breach they had back in 2013..

Yahoo, whose email service is also provided to BT and Sky customers, have confirmed that a breach they discovered in July last year affected all accounts. When investigating, it was discovered the breach occurred in 2013 and at first it was believed to have affected 500 million accounts.

Further investigation over the last year has found that the breach infected all 3 billion Yahoo user accounts, with 200 million user accounts and passwords found to be for sale on the dark web.

Yahoo, Sky and BT asked all users to change their passwords to prevent unwanted access to their users mailboxes.

Although changing the password prevents unwanted access to users mailboxes, it doesn?t prevent cybercriminals from using the account names and email addresses to send phishing emails. Phishing emails are increasing at an alarming rate with more users being tricked into clicking on dangerous links and attachments every year.

Cyber Wise recommends that anyone with a Yahoo, Sky or BT account should change the password to their email accounts.

We?d also like to remind all users to be on the lookout for suspicious emails. Recent figures show that 72% of breaches in the last 12 months were caused by fraudulent emails. It is imperative that all users know how to identify fraudulent emails and take the steps to ensure the safety of business and customer data.