A vulnerability has been identified in Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.3), Nucleus ReadyStart V4 (All versions < V4.1.0), Nucleus Source Code (Versions including affected DNS modules), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), SIMOTICS CONNECT 400 (All versions >= V0.5.0.0 < V1.0.0.0). The DNS client does not properly randomize DNS transaction IDs. That could allow an attacker to poison the DNS cache or spoof DNS resolving.
The software uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.