MZ Automation libiec61850 Out-of-bounds Read

The GOOSE payload parser contains a boundary handling flaw that can be
triggered by a single unauthenticated Layer 2 multicast frame on the
process bus. When processing specific payload fields, an attacker
controlled inner element length may exceed its enclosing length, causing
the parser to over read by one byte. This out-of-bounds read reliably
terminates the subscriber process, resulting in a denial-of-service
condition.