What is the default username and password to the oracle pre-built virtual machine?

The default password for the HR, sys and system accounts is oracle.

The Unix password for the oracle user is also oracle.

Okay, this is probably a better answer, since the objective is to be able to work with the 'system' database.

Use: sqlplus system as sysdba

and the password is -> oracle

I got in using student / student. This was in the Getting Started with EDQ pdf document, but it was not clearly designated that it worked for the sqlplus login.

[oracle@edqtrn ~]$ sqlplus system

SQL*Plus: Release 12.1.0.1.0 Production on Sat Aug 11 10:12:39 2018
    Copyright (c) 1982, 2013, Oracle.  All rights reserved.

Enter password: 
ERROR:
ORA-01017: invalid username/password; logon denied


Enter user-name: student

Enter password: 

Last Successful login time: Fri Aug 10 2018 23:57:35 -04:00

Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

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