The Brazilian was sent off during United's dramatic 3-2 Champions League comeback against Roma on Tuesday, but returned to the field after the final whistle to celebrate with his team-mates.
Manchester United staff were concerned that Cunha's actions could lead to further disciplinary consequences. Head coach Michael Carrick intervened and ordered the forward back towards the dressing room, with the visibly frustrated player eventually escorted down the tunnel.
UEFA has now confirmed that the incident will not result in an additional sanction.
"The UEFA official reports did not mention anything about this incident. Therefore the automatic one-match ban following two yellow cards should not be extended for this reason. We are not investigating further this matter," a spokesperson said.
Cunha was central to United's comeback at Old Trafford. After Bruno Fernandes converted a penalty to reduce Roma's early two-goal advantage, the forward scored twice to turn the match around and secure a vital victory.
His first booking came when he removed his shirt and celebrated by jumping into the Stretford End after scoring the winner. He was then shown a second yellow card in stoppage time for a foul on Leonardo Balerdi.
Carrick had been keen to prevent the situation from becoming more serious after Cunha returned to the pitch following his dismissal.
"I was disappointed with how it finished, but again just shows how much he cares and is willing to do," the United manager said.
"When he's in that frame of mind, he's in that mood and he plays like that, that's what we want from him. Matheus can do those things, you know. He's got those moments."
The incident brought back memories of Cunha's previous disciplinary trouble while at Wolves. He was charged by the Football Association after his dismissal in an FA Cup defeat against Bournemouth in March 2025, following a confrontation with Milos Kerkez.
On that occasion, he received an additional one-match ban and a £50,000 fine.
There will be no repeat of that outcome following Tuesday's events. Cunha will miss United's next Champions League fixture against Sporting Lisbon on November 25, but remains available for subsequent European matches.