Mason, a 24-year-old striker, scored five goals and registered one assist in 19 games this term. He spent the first-half of the season on loan with Bolton, returning to Wales in January and playing seven consecutive games at the end of the campaign.
However, he missed much of the season, and it appears as if the former Irish youth international is out of favour at Cardiff under manager Russell Slade. He may have brought him back into the fold late in the season, but Slade himself is keen on building a promotion winning team, and it does not appear as if he sees Mason as part of that.
This has led to the interest from Wolves, and Kenny Jackett is said to be keen on the 24-year-old, as he bolsters his attacking ranks ahead of another push for promotion next term.
Benik Afobe and Nouha Dicko are the biggest sources of goals, whilst Bakary Sako is leaving Molineux this summer. Jackett believes Mason is good enough to provide both cover and competition for his current attacking duo, whilst he is still young enough to keep improving.
The report states that the Midlands club are preparing a £3 million offer for Mason, and Cardiff could be willing to sell if approached with such a fee this summer.