A vulnerability has been identified in SIMATIC ET 200SP Open Controller CPU 1515SP PC (incl. SIPLUS variants) (All versions), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions <= 20.8), SIMATIC ET200SP (incl. SIPLUS variants) Open Controller CPU 1515SP PC (All versions), SIMATIC ET200SP (incl. SIPLUS variants) Open Controller CPU 1515SP PC2 (All versions), SIMATIC S7 PLCSIM Advanced (All versions <= V3.0), SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (All versions <= V4.4), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants), excluding CPU 1518 MFP (and related SIPLUS variant) (All versions <= V2.8.1), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants), excluding CPU 1518-4 PN/DP and CPU 1518 MFP (and related SIPLUS variant) (All versions <= V2.8.1), SIMATIC S7-1500 Software Controller (All versions <= V20.8). An attacker with network access to port 102/tcp could potentially modify the user program on the PLC in a way that the running code is different from the source code which is stored on the device. An attacker must have network access to affected devices and must be able to perform changes to the user program. The vulnerability could impact the perceived integrity of the user program stored on the CPU. An engineer that tries to obtain the code of the user program running on the device, can receive different source code that is not actually running on the device. No public exploitation of the vulnerability was known at the time of advisory publication.