De acordo com a novela de Alan Dean Foster, foi Ben.
A request that wouldn’t go away, he knew. It would never go away. He made up his mind. Instead of retreating, he advanced. Instead of running for safety, he took up the challenge. There was no real choice, he told himself as he advanced to the edge of the walkway. And called out.
“Ben!”
It echoed across the gap, reverberated through the vast open space below. On the far side, a tall figure turned and retraced his last few steps. “Han Solo.” Kylo Ren stared across at the older man. “I’ve been waiting for this day for a long time.”
“Take off that mask.” Han’s tone was a mix of command and empathy. “You don’t need it. Not here. Not with me.”
“What do you think you’ll see if I do take it off?”
Han moved forward slightly. “The face of my son.”
Por favor, note que seu sobrenome permanece (até agora) um mistério, já que Leia reteve seu sobrenome original de Organa no novo cânone da Disney, então Ben poderia ter sido Solo ou Organa.
Não encontrei detalhes sobre o sobrenome na novela, nem sobre os novos artigos visuais de dicionário, nem sobre o Databank.