The management report did not include cases that involved their peacekeepers, who have been riddled with accusations this year of misconduct and sexual abuse in the Central African Republic.
As of September, 17 UN peacekeepers have been accused of sexual exploitation in the region.
The UN mission "condemns in the strongest possible terms any instance of sexual exploitation and abuse committed by UN personnel in the CAR," they said in a statement.
No details were provided regarding the four staff members who were dismissed over the child pornography.
The staff member who was caught using an official UN vehicle to transport marijuana was busted with approximately 173 kilograms (381 pounds) of marijuana, Reuters reported.
"While the United Nations can and does follow up with Member States, the national authorities concerned have the sole prerogative in determining what, if any, investigations or proceedings are initiated against the individuals," U.N. spokesman Farhan Haq said in a statement.
He said it was also to the national authorities to determine "what, if any, update to provide to the United Nations."
