A security anchor for a portable electronic device having an opening includes a body configured to be engaged by a lock head of a lock, a first engagement element extending from the body and configured to be inserted into the opening of the portable electronic device, a second engagement element extending from the body and configured to be inserted into the opening of the portable electronic device, and a plunger positioned between the first engagement element and the second engagement element. The plunger is linearly slidable and subsequently rotated relative to the body to expand apart the first and second engagement elements.