Special Character in password
Works with single quotes.

[oracle@o71 ~]$ sqlplus u1/u1!@(description=(address=(protocol=tcp)(port=1521)(host=o71.balazs.vm))(connect_data=(service_name=min18_o71)))
-bash: !@: event not found
[oracle@o71 ~]$ sqlplus 'u1/u1!@(description=(address=(protocol=tcp)(port=1521)(host=o71.balazs.vm))(connect_data=(service_name=min18_o71)))'

SQL*Plus: Release 18.0.0.0.0 - Production on Sat Mar 2 09:07:54 2019
Version 18.5.0.0.0

Copyright (c) 1982, 2018, Oracle.  All rights reserved.

Last Successful login time: Sat Mar 02 2019 09:07:15 +01:00

Connected to:
Oracle Database 18c Enterprise Edition Release 18.0.0.0.0 - Production
Version 18.5.0.0.0

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