Musnad Ahmad 28:302

Hajjaj narrated to us, Ibn Abi Dhi’b narrated to us, and Yazid said: Ibn Abi Dhi’b informed us, from Al-Harith ibn Abd al-Rahman, from Abu Salamah, from Abdullah ibn Amr, from the Prophet (peace and blessings of Allah be upon him), who said: "The Messenger of Allah (peace and blessings of Allah be upon him) cursed the one who gives the bribe and the one who takes the bribe." Yazid said: "The curse of Allah be upon the one who gives the bribe and the one who takes the bribe."