During the execution of a PL/SQL procedure during which there is a table creation, I have obtained the following oracle error:
ORA-00600: internal error code, arguments: [kcbnew_3], , , , , , , 
Can you help me to understand this problem?
The ORA-600 error is an untrapped error in the Oracle database code. Many errors in the Oracle database code will cause a known error to be raised and returned to the user. If Oracle does not have a known error message to return to the user, it throws the generic ORA-600 error. The first argument (kcbnew_3 in your case) is the location in the database code that caused the unknown error.
In this case, the ORA-600 [kcbnew3] error is caused by a database block being reused when it should not be reused. There are a number of known bugs filed with Oracle Support on this issue. The solution is to apply the Oracle 126.96.36.199 or 10.1.0.2 patchsets.