The 26-year-old "Neighbors" actor and 35-year-old "Machete" actress were spotted kissing and cuddling on a yacht over the weekend.
The pair have been on vacation in Italy, and the boat was seen off the coast of Sardinia, an autonomous Italian island, on Saturday.
Efron and Rodriguez held hands and shared kisses, and the actor put an arm around Rodriguez as he stroked and kissed her hair.
The two enjoyed the sun and sea with Italian entrepreneur Gianluca Vacchi and several other friends.
Efron was linked to his "Neighbors" co-star Halston Sage earlier this year, while Rodriguez confirmed her relationship with Cara Delevingne in February. The actress refused to comment on her breakup with the model in June, telling a reporter, "I have no idea what you're talking about."
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