Problem:
ORA-01031: insufficient privileges
ORA-06512: at "SYS.DBMS_DEBUG_JDWP",
ORA-06512: at "SYS.DBMS_DEBUG_JDWP_CUSTOM".
Solution:
On problematic Oracle Server, for User with insufficient privileges , execute command:\
GRANT DEBUG CONNECT SESSION TO <User>
Background:
SELECT *
FROM dba_sys_privs
WHERE grantee='<User>'
order by privilege
SELECT *
FROM dba_role_privs
WHERE grantee='<User>'