Riether is the first player to be charged under a new pilot scheme where a panel of three former referees reviews video evidence of incidents not seen by match officials.
The German defender appeared to stamp on Januzaj in the last minute of Fulham's 3-1 defeat to United, but the incident was not seen by referee Lee Probert or his assistants.
Riether has until 6pm on Tuesday to respond to the charge.
Source: PA
Source: PA