From Sahih Bukhari (Hadith 6855):
Narrated Al-Qasim bin Muhammad:Ibn `Abbas mentioned the couple who had taken the oath of Lian. `Abdullah bin Shaddad said (to him), "Was this woman about whom Allah's Messenger (ﷺ) said, 'If I were ever to stone to death any woman without witnesses. (I would have stoned that woman to death)?' Ibn `Abbas replied," No, that lady exposed herself (by her suspicious behavior)
Reference: Bukhari 6855