A vulnerability has been identified in All other SIPROTEC 5 device types with CPU variants CP300 and CP100 and the respective Ethernet communication modules (All versions ), DIGSI 5 engineering software (All versions < V7.90), SIPROTEC 5 device types 6MD85, 6MD86, 6MD89, 7UM85, 7SA87, 7SD87, 7SL87, 7VK87, 7SA82, 7SA86, 7SD82, 7SD86, 7SL82, 7SL86, 7SJ86, 7SK82, 7SK85, 7SJ82, 7SJ85, 7UT82, 7UT85, 7UT86, 7UT87 and 7VE85 with CPU variants CP300 and CP100 and the respective Ethernet communication modules (All versions < V7.90), SIPROTEC 5 device types 7SS85 and 7KE85 (All versions < V8.01), SIPROTEC 5 device types with CPU variants CP200 and the respective Ethernet communication modules (All versions < V7.59), SIPROTEC 5 relays with CPU variants CP200 and the respective Ethernet communication modules (All versions < V7.59). Specially crafted packets sent to port 443/TCP could cause a Denial of Service condition.