Code
T3008 incoming-not-verified
A call coming in states neither verify nor open: whoever finds its address would start its flow.
Details
An incoming either checks the signature of what arrives, with verify, or says why it takes calls that nobody signed, with open: 'why'. The finding stands at the line of the definition.
The fix
State verify with the signature of its sender, or open: 'why' where nobody can sign it.