The offence was committed near Linn Park’s waterfall viewpoint at around 6pm on Friday, October 22.
The suspect is described as white, in his late 30s, around 6ft1 and of very slim build with a bald head.
He was wearing a plain white vest and electric blue basketball-style shorts with white leggings underneath.
Detective Sergeant Nikki McPherson, of Glasgow CID, said: “Clearly, this was a disturbing and upsetting incident for the woman involved, who thankfully reported the matter to police.
“We are asking the public to get in touch if they think they know who this man is, or have witnessed similar incidents recently. We will be carrying out extensive enquiries to find the man responsible.
“Anyone with information that could assist our enquiries should call police via 101, quoting incident 2978 of October 22.”