MZ Automation libiec61850 Out-of-bounds Read

The MMS BER decoder contains a boundary-handling flaw in the processing
of certain fields within confirmed-request messages. When a crafted
BER-encoded element is received over an established MMS session (TCP
port 102), the decoder may advance its internal read position
incorrectly, leading to a heap out-of-bounds read. This condition causes
the MMS handling process to terminate unexpectedly, resulting in a
denial-of-service.