Salihi helped fill the scoring void left by Nikica Jelavic, who left Rapid Vienna for Rangers in a £4million deal 18 months ago.
Celtic boss Neil Lennon has confirmed the club is interested in the 27-year-old striker.
He said: “He is a player we have known about from the Jelavic days. He might be an option.”
Salihi is expected to leave Rapid Vienna in January after failing to agree a contract extension with the club.
Rapid Vienna coach Peter Schoettel said: “Rapid are open to having transfer talks over Hamdi. If there is a matching offer he can go.”
