The install-amd64-minimal-20170907.iso (and I assume other media) does not have support for SMB2/3. Please enable the following Kconfig options: CONFIG_CIFS_SMB2=y CONFIG_CIFS_SMB311=y
With Linux 4.13 and later there is no CONFIG_CIFS_SMB2. Enabling CONFIG_CIFS will also enable support for SMB2/3.