A vulnerability has been identified in SIMATIC CP 343-1 Advanced (All versions), SIMATIC CP 343-1 Standard (All versions), SIMATIC CP 443-1 Advanced (All versions), SIMATIC CP 443-1 Standard (All versions), SIMATIC S7-1500 Software Controller incl. F (All versions < V1.7.0), SIMATIC S7-1500 incl. F (All versions < V1.7.0), SIMATIC S7-300 incl. F and T (All versions < V3.X.16), SIMATIC S7-400 H V6 (All versions < V6.0.9), SIMATIC S7-400 PN/DP V6 Incl. F (All versions < V6.0.7), SIMATIC S7-400 PN/DP V7 Incl. F (All versions), SIMATIC S7-410 (All versions < V8.1), SIMATIC WinAC RTX (F) 2010 (All versions < SIMATIC WinAC RTX 2010 SP3), SINUMERIK 828D (All versions < V4.7 SP6 HF1), Softnet PROFINET IO for PC-based Windows systems (All versions). Responding to a PROFINET DCP request with a specially crafted PROFINET DCP packet could cause a Denial-of-Service condition of the requesting system. The security vulnerability could be exploited by an attacker located on the same Ethernet segment (OSI Layer 2) as the targeted device. Successful exploitation requires no user interaction or privileges and impacts the availability of core functionality of the affected device. A manual restart is required to recover the system. At the time of advisory publication no public exploitation of this security vulnerability is known. Siemens provides mitigations to resolve the security issue. PROFIBUS interfaces are not affected.