Narrated `Aisha: Some people asked Allah's Messenger (ﷺ) about the fore-tellers. Allah's Messenger (ﷺ) said to them, "They are nothing (i.e., liars)." The people said, 'O Allah's Messenger (ﷺ) ! Sometimes they tell something which comes out to be true." Allah's Messenger (ﷺ) said, "That word which comes to be true is what a jinx snatches away by stealing and then pours it in the ear of his fore-teller with a sound similar to the cackle of a hen, and then they add to it one-hundred lies."
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مُحَمَّدُ بْنُ سَلاَمٍ، أَخْبَرَنَا مَخْلَدُ بْنُ يَزِيدَ، أَخْبَرَنَا ابْنُ جُرَيْجٍ، قَالَ ابْنُ شِهَابٍ أَخْبَرَنِي يَحْيَى بْنُ عُرْوَةَ، أَنَّهُ سَمِعَ عُرْوَةَ، يَقُولُ قَالَتْ عَائِشَةُ سَأَلَ أُنَاسٌ رَسُولَ اللَّهِ صلى الله عليه وسلم عَنِ الْكُهَّانِ فَقَالَ لَهُمْ رَسُولُ اللَّهِ صلى الله عليه وسلم " لَيْسُوا بِشَىْءٍ ". قَالُوا يَا رَسُولَ اللَّهِ فَإِنَّهُمْ يُحَدِّثُونَ أَحْيَانًا بِالشَّىْءِ يَكُونُ حَقًّا. فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " تِلْكَ الْكَلِمَةُ مِنَ الْحَقِّ يَخْطَفُهَا الْجِنِّيُّ، فَيَقُرُّهَا فِي أُذُنِ وَلِيِّهِ قَرَّ الدَّجَاجَةِ، فَيَخْلِطُونَ فِيهَا أَكْثَرَ مِنْ مِائَةِ كَذْبَةٍ ".
sunnah.com