The German website motorsport-total.com reported leaks about the Briton’s secret Ferrari visit have been made to the Italian media.
The report said Horner met with Ferrari’s head of human resources, Mario Mairano, probably last month.
“The thought is that this is an attempt to indirectly gain access to the services of star designer Adrian Newey,” wrote journalist Christian Nimmervoll.
It is believed Horner and Newey always sign and renew their Red Bull contracts together.
Horner, understood to have a Red Bull contract until at least 2014, has also been previously linked to Ferrari team boss Stefano Domenicali’s job.