The invention relates to a safety device, for avoiding stab wounds, for a syringe with a syringe body and with a puncturing means arranged at the distal end of the syringe body, said safety device comprising a sleeve element which extends along an axial direction (X) and at least partially encloses the puncturing means and the syringe body, wherein the sleeve element comprises, at its distal end, a contact portion which at least partially contacts the skin of a patient during use of the syringe and which delimits an opening surface. The safety device is characterized in that the opening surface has at least in part a sub-area that encloses an angle α with the axial direction (X), wherein the angle α is in a range of between 10° and 80°.