The Red Devils only managed a 2-2 draw with Bolton on Sunday and have drawn all three games on their travels this season.
“It is a big concern that we are conceding so many away goals,” said Vidic. “We have to stop doing it. We cannot let it happen again.
“Over the last few years we haven’t given that many goals away or even allowed them so many chances.
“Before we have always looked strong, so this is not what we are used to.
“We have to play much better in our away games.”