Reports suggesting the two singers are dating surfaced earlier this year (14), following posts and photos on social media linking the two, but Cabello has now finally confirmed the rumours.
During an appearance on U.S. late night talk show Watch What Happens Live on Monday (03Nov14), host Andy Cohen probed the girl group about whether they have ever dated fellow pop stars such as members of One Direction or 5 Seconds of Summer.
Then the host added, "Hold on, who's the Mahone girlfriend?" to which Cabello held up her hand and said, "That would be me."
Cohen insisted she must be a real "Mahomie", fan of the pop star, and Cabello agreed, saying "He's a really good guy", but refused to divulge further details of their relationship.
On Tuesday (04Nov14), Mahone took to Twitter.com and joked with his followers about the confirmation of their romance, writing, "Like you guys didn't know already."
Mahone has been previously linked to singers Selena Gomez and Becky G.