Sabotaging Material Extrusion-Based 3D Printed Parts through Low-Magnitude Kinetic Manipulation Attacks

The increasing ubiquity of material-extrusion-based additive manufacturing is motivating cybersecurity researchers to explore its offensive and defensive landscape. Being a physical system, 3D printers have non-zero tolerance specifications for precision and trueness parameters. While a single-bit change in a digital data file is sufficient to fail its integrity and is easily detected through methods such as hashing, the printing process (and subsequently the printed object) remains compliant within the tolerance zone. This study systematically analyzes the material extrusion process and identifies four attack opportunities where low-magnitude kinetic cyberattacks exploit the physical process compliance zone to sabotage the printed part’s mechanical properties. The attacks are demonstrated on ASTM-compliant tensile and flexure bars through a man-in-the-middle attack scenario by hijacking the network layer communication between the 3D printer and the printer control machine. The physically stealthy attacks did not produce any evident deformation in the parts’ dimensions and mass, while the destructive tests confirm that they are still effective in modifying the tensile and bending strength by up to 25%. The effectiveness of the attacks in bypassing the defenses is assessed by implementing one of the leading detection schemes described in the current literature. The attacks were either not detected at all or detected with a significantly high false negative rate at various attack magnitudes.