A vulnerability has been identified in SCALANCE X-200 switch family (incl. SIPLUS NET variants) (All Versions), SCALANCE X-200IRT switch family (incl. SIPLUS NET variants) (All versions). Devices create a new unique key upon factory reset, except when used with C-PLUG. When used with C-PLUG the devices use the hardcoded private RSA-key shipped with the firmware-image. An attacker could leverage this situation to a man-in-the-middle situation and decrypt previously captured traffic.