Two men were sat in a car on School Road in Brierley Hill at around 8pm on Monday when a group smashed the windows and dragged the driver out, West Midlands Police said.
The driver was stabbed multiple times but police say his injuries are not thought to be serious.
The passenger also suffered minor injuries during the attack and was taken to hospital.
Police said today that they are investigating whether the victims were deliberately targeted in what was the latest of a spate of knife attacks in the region.
Meanwhile last week a youth was attacked with a knife and machete in Halesowen.
A spokesman for West Midlands Police said: "We are investigating reports of a stabbing on School Road, Quarry Bank at 8pm yesterday.
"Two men were sat in a car when a group approached them, smashing the windows before dragging the driver out of the car.
"He was stabbed multiple times and taken to hospital to be treated for his injuries, which fortunately are not thought to be serious.
"The passenger also suffered minor injuries after being assaulted during the disorder.
"We’re reviewing CCTV as part of our ongoing investigation."
An ambulance was sent to Birch Avenue, which is next to School Road.
Jamie Arrowsmith, spokesman for West Midlands Ambulance Service, said: “We were called at 8.15pm last night to reports of a stabbing on Birch Avenue, Brierley Hill. One ambulance and a paramedic officer were sent to the scene.
"On arrival we discovered two patients. One of whom, a man, was treated for multiple stab wounds, not believed to be life-threatening. He was then taken to hospital for further treatment.
"A second man was also assessed at the scene and taken to hospital for further treatment.”
Anyone with information is asked to contact police via Live Chat online or by calling 101.