We can see that "4f525245" is hex for "ERR". Indeed the return code from smb.smb_read is not checked and the code tries to parse smb_header as a header, whereas in this case it contains an error message.
I copied the code from a few lines above to properly handle the case where the connection is reset.
The result is now:
Host script results:
|_smb-vuln-ms17-010: SMB: ERROR: Server disconnected the connection
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