Officials say he is suspected of committing suicide, but members of his family have reportedly raised suspicions about bruises on his body.
"The commission will be headed by retired supreme court judge justice Javed Iqbal and will submit its report in two weeks," Interior Minister Rehman Malik told reporters late Sunday.
The commission can summon anyone from the police, NAB or other departments, the minister said.
NAB have confirmed Faisal was an investigations officer working on the case against Ashraf, whose arrest was ordered by the Supreme Court last week. The court has since adjourned the case to January 23.