Two major banks have identified fraudulent activity on a number of credit cards of customers as a result of the LoyaltyBuild cyber attack.
The Irish Independent reports that both AIB and Permanent TSB have confirmed that a number of their customers have been affected.
More than 80,000 Supervalu, Axa and Stenal Line loyalty programme customers have had their credit card details compromised as a result of the European-wide online attack.
Meanwhile, some of Electric Ireland's customer email details have been taken.
Tom Brady, the Irish Independent's Security Editor, told Newstalk's Breakfast that more companies are likely to admit they've been affected over the coming days