Dentsu’s US subsidiary Merkle hit by cyberattack, staff and client data exposed

According to Dentsu, its U.S.-based subsidiary Merkle suffered a cyberattack that exposed staff and client data and prompted parts of its network to be taken offline as a precaution. The firm says it detected abnormal activity, initiated incident response procedures, and has since restored affected systems while external cybersecurity help investigates and authorities in impacted countries have been notified.

The breach involved files from Merkle’s network containing information about current and former employees, including bank and payroll details, salary, National Insurance numbers, and personal contact details. Dentsu notes that the network in Japan was not impacted. It remains unclear whether Merkle was targeted by ransomware, and no ransomware group has claimed responsibility for the attack.

Merkle, a U.S.-based marketing and customer experience agency, employs over 16,000 people globally, with Dentsu indicating the group continues to assess the financial impact of the incident.