Customers impacted were merchants, campus diners and diners who interacted with their customer care service, Grubhub said.

Popular food delivery company Grubhub announced it suffered a security breach involving a "third-party actor." Here's what it means.

It’s not clear how many users were impacted by the data breach, though Grubhub notes that “contact information of campus diners, as well as diners, merchants and drivers who interacted with our customer care service” was accessed.

Grubhub, the food delivery service, has been hacked. On Monday, the company confirmed a data breach that affects both its drivers and customers. According to Grubhub, the malicious actor was able to gain entry into its systems via a third-party vendor that provides services for Grubhub's support team.

Grubhub says that it noticed “unusual activity” that it traced back to an account used by a third-party service provider for its customer support team. The account’s access