NEW DELHI—Personal data of an unspecified number of travelers has been compromised after a company that serves India’s national carrier was hacked, Air India said. The hackers were able to access 10 years’ worth of data including names, passport and credit card details from the Atlanta-based SITA Passenger Service System, Air India said in a statement Friday. It disclosed the scale of the breach nearly three months after it was first informed by the IT provider. The breach that happened in late February had compromised the data of some major global airlines, too. SITA at that time had said that Singapore Airlines, New Zealand Air and Lufthansa were among those affected. Air India said almost 4.5 million passengers globally were affected in the “highly sophisticated” attack but did not specify how many of them were its travelers. It said no password data was breached during the attack and that the …