It is narrated from Sayyiduna Thawban (may Allah be pleased with him) that he said: The Messenger of Allah (peace and blessings be upon him) cursed the one who takes a bribe, the one who gives a bribe, and the one who acts as a go-between for them.
Hadith Referenceالمعجم الكبير للطبراني / باب الثاء / 1402