said a ransomware attack at a third-party software supplier has disrupted its system for tracking employee payments, forcing the coffee giant to manually track workers' scheduling and hours.

, a subsidiary that provides supply chain management software, said its systems were disrupted by a Nov. 21 "ransomware incident." Starbucks is among its customers and used Blue Yonder software to schedule shifts and track retail workers' hours in North America, a company spokesperson said.

Starbucks' stores are resorting to manual methods such as pen and paper for employee scheduling, the spokesperson said, adding that ...