Abu Hatim ibn Hibban al-Busti: He inverts narrations and attributes suspended narrations (to the Prophet). It is not permissible to use his narrations as evidence if he is the sole narrator.
Abu Zur'a al-Razi: He narrated fabrications.
al-Daraqutni: He weakened him.
Muhammad ibn Ishaq ibn Mandah al-Asbahani: He narrated Munkar narrations, there is weakness in him.