What a person should do if he stands up after two rak'ahs and forgets to say the tashahh
باب مَا يَفْعَلُ مَنْ قَامَ مِنَ اثْنَتَيْنِ نَاسِيًا وَلَمْ يَتَشَهَّدْ
Sunan an-Nasa'i, Book of Forgetfulness (In Prayer)(view book)
It was narrated that Abdullah bin Buhainah said:
"The Messenger of Allah ﷺ led us in praying two rak'ahs, then he stood up and did not sit, and the people stood up with him. When he finished the prayer, and we were waiting for him to say the taslim, he said the takbir and prostrated twice while sitting, before the taslim. Then he said the taslim."
أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَبْدِ الرَّحْمَنِ الأَعْرَجِ، عَنْ عَبْدِ اللَّهِ ابْنِ بُحَيْنَةَ، قَالَ صَلَّى لَنَا رَسُولُ اللَّهِ ﷺ رَكْعَتَيْنِ ثُمَّ قَامَ فَلَمْ يَجْلِسْ فَقَامَ النَّاسُ مَعَهُ فَلَمَّا قَضَى صَلاَتَهُ وَنَظَرْنَا تَسْلِيمَهُ كَبَّرَ فَسَجَدَ سَجْدَتَيْنِ وَهُوَ جَالِسٌ قَبْلَ التَّسْلِيمِ ثُمَّ سَلَّمَ .
Classification
It was narrated from 'Abdullah bin Buhainah that:
The Messenger of Allah ﷺ stood up during the prayer when he should have sat, so he prostrated twice while sitting, before the taslim.
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ هُرْمُزَ، عَنْ عَبْدِ اللَّهِ ابْنِ بُحَيْنَةَ، عَنْ رَسُولِ اللَّهِ ﷺ أَنَّهُ قَامَ فِي الصَّلاَةِ وَعَلَيْهِ جُلُوسٌ فَسَجَدَ سَجْدَتَيْنِ وَهُوَ جَالِسٌ قَبْلَ التَّسْلِيمِ .