Is it true that the real powers lie in the hands of the permanent members of the Security Council?

Yes, it is true that the real powers lies in the hands of the permanent members of the Security Council.

Each permanent member has a veto power. This means that if any decision is supposed to be taken and any permanent member disagrees to the outcome of the decision, the Council cannot take pass the decision. This is gives them the upper hand as compared to the member nations.