Hadithcore
Sahih al-Bukhari, 4249
sahih

Narrated Abu Huraira:

When Khaibar was conquered, a (cooked) sheep containing poison, was given as a present to Allah's Messenger.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، حَدَّثَنَا اللَّيْثُ، حَدَّثَنِي سَعِيدٌ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ لَمَّا فُتِحَتْ خَيْبَرُ أُهْدِيَتْ لِرَسُولِ اللَّهِ صلى الله عليه وسلم شَاةٌ فِيهَا سُمٌّ‏.‏

References2 variants
In-Book Reference
Book 64, Hadith 284
USC-MSA web (English) reference
Vol. 5, Book 59, Hadith 551 (deprecated numbering scheme)