Jami` at-Tirmidhi 721
جامع الترمذي#721SahihAbu Hurairah narrated that the Messenger of Allah said:"Whoever eats or drinks forgetfully, then he has not broken (the fast), for it was only a provision that Allah provided for him
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih
In-book reference: 8:40