Vidic remained in Manchester when United headed off to South Africa and China last month.
However, the Serbian has now completed his recovery from a cruciate operation and will be around to bolster Ferguson's defensive options at a time when both Jonny Evans and Chris Smalling are on the sidelines.
In addition, Brazilian full-back Rafael is still on international duty, meaning Ferguson only has four first-choice defenders available following the return of his Euro 2012 contingent.
"Chris Smalling is out for 10 weeks with his metatarsal operation and Jonny Evans is still just in light training," Ferguson told the club's website.
"They are big losses and they will miss the start of the season.
"Rafael is away but we do have Phil Jones, Nemanja Vidic, Rio Ferdinand and Patrice Evra.
"That will be the back four on tour.
"Hopefully we don't get any more injuries as it would leave me a bit short."
United face Norwegian outfit Valerenga on Sunday, then Barcelona in Gothenburg on Wednesday before concluding their pre-season programme away to Bundesliga side Hannover on August 11.
It is anticipated goalkeeper David de Gea will also join the United party earlier than anticipated following Spain's shock group stage Olympic exit.
