Wessels is ruled out for South Africa's upcoming test matches.
South Africa front-rower Wessels faces a suspension of nine matches for making contact with Josh Murphy's private parts during the Blue Bulls' URC victory over Connacht.
The altercation occurred in the 18th minute of the close contest in Galway on last Friday, with opposing player Murphy receiving a temporary dismissal after responding aggressively by hitting Wessels on the head.
Following the Connacht player reported the incident to referee Mike Adamson, the event was examined by the television match official, who concluded no conclusive video evidence.
The Bulls player remained on the pitch until he was substituted in the later stages of the game.
Although the URC confirmed that the Irish player's temporary sending-off was withdrawn by a disciplinary panel, the Springbok was deemed to have breached law 9.27, which declares:
"Any athlete must not do anything that is against the principles of fair play. Such behavior covers grabbing, pulling or squeezing the private areas."
Disciplinary officials concluded that the event reached the red card threshold and justified a three-month ban, the shortest ban under World Rugby rules for such an infringement.
However, the player's suspension was shortened by three weeks because of his cooperative behavior prior to and at the proceedings and his clean disciplinary history.
Wessels and the Pretoria-based team have the right to appeal, but as it stands, the ban will prevent the 24-year-old out of the South African national team's fall internationals against Japan, France, Italy and Ireland.
Wessels will additionally be absent for the his club's URC games against Warriors, the Lions and the Cell C Sharks, as well as European cup fixtures with Bègles and Saints.
Wessels has won ten international appearances for South Africa and was included in their Rugby Championship-winning squad over the summer.
Murphy, in contrast, is available to play against Munster in Saturday's inter-provincial derby after being cleared.