The incident happened outside Majestic Wine on North Street between 9.45pm and 10pm on Wednesday, May 4.
The victim was approached by two unknown young men who punched him several times in an unprovoked attack.
He suffered minor facial injuries which did not require medical treatment.
The suspects are described as being aged around 16 to 18 years old and were wearing dark tracksuits.
Anyone with any information that could assist the investigation should contact North Yorkshire Police on 101, select option two, and ask for Mark Nursey.
You can also email [email protected]
If you wish to remain anonymous, you can pass information to Crime stoppers by calling 0800 555 111.
Quote the North Yorkshire Police reference number 12220075828 when providing information.