The two strikers are both suffering with knocks ahead of Saturday's home game against Cardiff City, while Micah Richards is set to miss his sixth straight match due to a knee problem.
Aston Villa failed to win against Newcastle United in the Championship on Saturday.
Aston Villa's Ritchie De Laet faces a spell on the sidelines.
The Villans will be without the Belgian for the rest of the campaign.
McCormack is only expected to miss Saturday's match at Ipswich Town, but De Laet is facing a much lengthier spell out.
The 27-year-old Belgian right-back played 70 minutes in Saturday's 3-1 loss at Bristol City.
The 27-year-old Belgian defender joined the Championship side from Leicester City on Wednesday on a three-year deal.
The Belgian says he is looking forward to having some fun with his new teammates after completing a move from Leicester City.
The former Leicester City defender has joined the Tony Xia revolution at Villa.
The defender joined Villa on a three-year deal from Leicester City on Tuesday,