1. A method of determining security risks, comprising: retrieving a plurality of account credentials indications stored on a plurality of members of a first group of machines in a network; collecting a plurality of account access rights, each one of said plurality of account access rights grants an access to at least one member of a second group machines in said network; and identifying at least one of a presence and absence of a plurality of security risks to at least one member of said second group by a correlation between at least one of said plurality of account credentials indications and at least one of said plurality of account access right; wherein said at least one account credentials indication and said at least one account access right is of the same account.