Boston Scientific disclosed in a filing with the U.S. Securities and Exchange Commission on Wednesday that it had been hit by a cyberattack that affected business operations. According to Sina Finance, the company said the attack disrupted access to its information systems and business applications, including shipping-related services, and that the timing of full system restoration remains unclear.

Boston Scientific shares fell 4.5% in early trading on Wednesday after the disclosure. The medical device maker, which produces pacemakers and stents, said it was working to restore affected functions and system access. Piper Sandler analyst Matt O'Brien said after speaking with management on Wednesday morning that Boston Scientific may need several weeks to return to normal operations, and he wrote that the company could restore all product shipments within three weeks.