The incident happened in the High Street near its junction with Almon Place, at 10.50pm on Saturday 27 August 2022.
It is alleged a man was punched by a woman he did not know as he left a public house. He suffered serious facial injuries and later went to hospital for medical attention.
Detective Sergeant Colin Cherry, of Medway CID, said: ‘This was a violent and unprovoked assault and we have been completing enquiries to identify the person responsible.
‘We are now able to release an image of a woman who may be able to assist with our enquiries. While it is blurred we are hoping somebody who recognises the person contacts our appeal line.’
Anyone with information should call Kent Police on 01634 792209, quoting crime reference 46/170023/22.
You can also call Crimestoppers anonymously on 0800 555111 or complete the online form on their website at www.crimestoppers-uk.org