Sahih al-Bukhari 5936
صحيح البخاري#5936Sahihحَدَّثَنَا آدَمُ، حَدَّثَنَا شُعْبَةُ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنِ امْرَأَتِهِ، فَاطِمَةَ عَنْ أَسْمَاءَ بِنْتِ أَبِي بَكْرٍ، قَالَتْ لَعَنَ النَّبِيُّ صلى الله عليه وسلم الْوَاصِلَةَ وَالْمُسْتَوْصِلَةَ.
Narrated Asma':(the daughter of Abu Bakr) Allah's Messenger (ﷺ) has cursed such a lady as artificially lengthening (her or someone else's) hair or gets her hair lengthened
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 77:151