Tesco is being forced to reissue more than 600,000 Clubcards after they were hit with “fraudulent activity” exposing customer information.
The UK’s largest grocer emailed 620,000 Clubcard holders to inform them that hackers had accessed username and password combinations from another website and attempted to access Tesco sites “where customers used the same” details.
While Tesco assured those affected that no financial information had been jeopardised, it encouraged those affected to change their passwords immediately.
It added that the decision to reissue hundreds of thousands of Clubcards was a precautionary measure and that no one would lose their loyalty points.
“We are aware of some fraudulent activity around the redemption of a small proportion of our customers’ Clubcard vouchers,” it said in a statement.
“We have strict security measures in place and our priority is protecting our customers.
“Our internal systems picked this up quickly and we immediately took steps to protect our customers and restrict access to their accounts.
“At no point was any customer’s financial data accessed.
“We believe that someone has stolen password/username combinations from other website(s) and used them to try to access Tesco sites – where customers used the same username and password.”
It is understood that around 19 million people currently hold a Tesco Clubcard, which offers a one per cent cashback on all items purchases instore.