The invention relates to a cage nut (10, 110) comprising a nut (14, 114) which is arranged in a cage (12, 112). The cage (12, 112) has a base (16, 116) that has a round hole out of which two opposing lateral parts (18, 118) rise, each lateral part having a support portion (20, 120) oriented outwards. The cage (12) and the nut (14) have diametrically opposing attachments which are formed such that the nut, which is inserted into the cage, can be partly inserted axially into a non-round opening, preferably a quadratic opening, in a thin wall in a specified rotational position in the event of an emergency after the lateral parts have been pressed together, and the screw (30) can then be screwed into the nut (14).