The attack happened around 8:50 a.m. near the Kukio Resort Club House on Hawaii Island when the victim, who has not been identified, was about 200 yards offshore with an ocean excursion group of 17 people, said the Hawaii Department of Land and Natural Resources (DLNR).
The victim was one of two members of the group swimming, while eight others were on stand-up paddleboards and six others in canoes.
Before the attack, a jet ski operator told the group that a 10-foot Tiger shark was in the area, officials said.
The shark approached the 57-year-old woman from behind and bit her, leaving an approximately 2-inch puncture wound to her left knee, the Hawaii Tribune-Herald reported, citing the Hawaii Fire Department.
The injured woman was brought into one of the canoes and taken to shore and given first aid. She was later treated at the North Hawaii Medical Center, where she was in stable condition, West Hawaii Today reported.
Officials closed the beaches for the rest of the day, according to the reports.
While some species of shark are known to move inshore to feed at dusk, dawn, and at night, tiger sharks are known to bite people at all times of day, the DLNR said in a list of safety tips to reduce the risk of injuries caused by sharks.