A woman reported she was approached by a man near the junction of College Drive as she walked along Sandrock Road between 6.30pm and 7pm on Tuesday 5 November 2024.
The man touched her inappropriately over her clothes before leaving the scene in the direction of the town centre.
Investigators are now able to release a computer generated image of the suspect.
Anyone with information is urged to call the west Kent appeals line on 01622 604100, quoting reference 46/189328/24.
Local residents with private CCTV and drivers with dashcam, who may have been in the area at the time of the incident, are also asked to check for relevant footage.
You can also call Crimestoppers anonymously on 0800 555111 or complete their online form.