[asterisk-users] 500 Server Error on <Null> Caller ID

[CDR]

When a client send me an INVITE with this type of caller ID
From: "eurus" <sip:<null>@XX.XX.XX.XXX>;tag=3430296121-3809549020-352327076-1077499159
Asterisk 14 sends back

SIP/2.0 500 Server error occurred (1/SL)

My client says
"Yes,  I know the null is there but this not illegal and perfectly
acceptable according to rfc 3261. "

Should I open a bug ticket?