A card reading assembly for a self-service terminal includes a storing compartment for a card containing data to be read. The self-service terminal includes at least one sensor and an evaluation device connected hereto and the card reading assembly is protected against manipulation attempts by arranging at least one sensor in the card reading assembly and at least one linearly extending sensor arrangement that is attached in the storing compartment. The evaluation device checks at least one spatial dimension of the card via the sensor arrangement. Preferably, the sensor system is a sensor arrangement including a plurality of linearly extending sensor elements that extend in a first direction or a second direction in relation to the card retracted into the storing compartment. It can be effectively determined whether a retracted card is a genuine card of if a manipulation is present that targets the inside of the card reading assembly.