Race condition

A vulnerability has been identified in SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions >= V2.5 and < V20.8), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions >= V2.5 and < V2.8), SIMATIC S7-1500 Software Controller (All versions >= V2.5 and < V20.8). Affected devices contain a vulnerability that allows an unauthenticated attacker to trigger a Denial-of-Service condition. The vulnerability can be triggered if specially crafted UDP packets are sent to the device. The security vulnerability could be exploited by an attacker with network access to the affected systems. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise the device availability.