It is narrated from Sayyiduna Uqbah bin Amir (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "After me there will be rulers (umara) who will lead you in prayer. If they complete its bowing and prostration, then (the reward) is for you and for them; and if they fall short in them, then (the reward of your prayer) is for you and (the burden of the shortcoming) is upon them."
Imam al-Tabarani (may Allah have mercy on him) said: "This hadith was narrated from Abd al-Rahman bin Harmalah, from Sa'id bin al-Musayyib, only by Attaf bin Khalid, and Ali bin Hafs al-Mada'ini is alone in narrating it."
Yahya bin Ayyub al-Misri and others narrated it from Abd al-Rahman bin Harmalah, from Abu Ali al-Hamdani Thumamah bin Shufayy, from Sayyiduna Uqbah bin Amir (may Allah be pleased with him), from the Prophet (peace and blessings be upon him), with something similar.
Hadith Referenceالمعجم الأوسط / باب العين / 4139
Hadith Gradingمحدثین:إسناده ضعيف
Hadith Takhrij«قال ابن رجب الحنبلي: في هذا الإسناد ضعف «فتح الباري شرح صحيح البخاري لابن رجب، ج 3، ص 22»» «أخرجه أحمد فى «مسنده» برقم: 17596، والطبراني فى «الكبير» برقم: 955»