I'm using Oracle 11g(11.2.0.1.0). I created about 20 tablespaces and users. And the data came by [Tools] - [Database Copy] on Oracle SQL Developer.
Somehow I found that a user is using SELECT query on the table from another schema. I want to prevent it for security. How should I change my grant options?
I read "Oracle Database Security Guide 11g Release 2(11.2)", but couldn't find the solution clearly.
Here are my creating and granting queries.
create user [USER_NAME]
identified by [PASSWORD]
default tablespace [TABLESPACE_NAME]
temporary tablespace TEMP;
grant create session,
create database link,
create materialized view,
create procedure,
create public synonym,
create role,
create sequence,
create synonym,
create table,
drop any table,
create trigger,
create type,
create view to [USER_NAME];
alter user [USER_NAME] quota unlimited on [TABLESPACE_NAME];
And here is the SELECT result of session_privs on a user.
SQL> SELECT * FROM session_privs;
PRIVILEGE
--------------------------------------------------------------------------------
CREATE SESSION
CREATE TABLE
DROP ANY TABLE
CREATE SYNONYM
CREATE PUBLIC SYNONYM
CREATE VIEW
CREATE SEQUENCE
CREATE DATABASE LINK
CREATE ROLE
CREATE PROCEDURE
CREATE TRIGGER
PRIVILEGE
--------------------------------------------------------------------------------
CREATE MATERIALIZED VIEW
CREATE TYPE
13 rows selected.
I want to prevent a user from querying SELECT on other schemas.
For example, the following query
-- connected with USER1
SELECT *
FROM USER2.table1;
should make an error like:
ERROR: USER1 doesn't have SELECT privilege on USER2.
Edited:
Use appropriate terms (changed some words from tablespace to schema)
Add SELECT result of session_privs on a user
Add the method of how the data came by.
It was my fault. I missed that I had added some roles.
To copy data using Oracle SQL Developer, I added predefined roles to users. The roles were exp_full_database and imp_full_database.
According to Oracle Database Security Guide: Configuring Privilege and Role Authorization, exp_full_database contains these privileges:
SELECT ANY TABLE
BACKUP ANY TABLE
EXECUTE ANY PROCEDURE
EXECUTE ANY TYPE
ADMINISTER RESOURCE MANAGER
INSERT, DELETE, UPDATE ON SYS.INCVID, SYS.INCFIL AND SYS.INCEXP
and roles:
EXECUTE_CATALOG_ROLE
SELECT_CATALOG_ROLE
Those roles are not required now. So the answer is removing them from users.
REVOKE exp_full_database, imp_full_databsae FROM USER1;
And I get the result I wanted.
-- connected with USER1
SELECT * FROM USER2.TABLE1;
ERROR at line 1:
ORA-01031: insufficient privileges
Related
I use windows 7 and oracle 11g , so when i created user test and give an him create table privilege:
grant create table to test;
I notice that this user can also do select,insert,delete on the table that he created but i don't give him any object privileges.
is create table privilege mean all object privileges are granted?
Table owner can do everything with that table - all DML and DDL actions (selects, inserts, updates, deletes, alters, drops, ... everything).
If you want to let other users do something with your tables, then you'll have to grant those privileges to them.
I'm creating a USER on Oracle 12 c database, using TOAD.
After creating the TABLESPACE, I'm creating the USER. I'm a little confusing about the many ROLES and PRIVILEGES that can be given to a USER.
What are the minimum/standard roles and privileges a user must be given in order to perform CRUD operation and being able to 'edit' the database (create or delete table, DROP the schema ecc) from TOAD?
Thank you
It depends on what operations are you going to perform. If you want to work only with tables in your own db schema, then the following privileges are usually enough to start:
grant create session to <your_user>;
grant create table to <your_user>;
You have the default rights to insert/update/delete/select tables which you own.
Tablespace quota:
alter user <your_user> quota unlimited on <your_tablespace_name>;
It's better to set the default tablespace for the user. In this case you can omit the tablespace name in a create table statement.
alter user <your_user> default tablespace <your_tablespace_name>;
A link to the documentation - Privileges
Grant the user the following privileges:
CREATE SESSION (in order to allow the user to connect to the database)
INSERT
UPDATE
DELETE
SELECT
Use the below command to grant privileges to the user (you need to login as SYS or SYSTEM or another user that has GRANT privilege):
GRANT CREATE SESSION, SELECT, UPDATE, DETETE, INSERT TO user_name
Here's a suggestion you might (or might not) want to follow.
As a privileged user (such as SYS), check tablespaces available in your database. I'm using 11g XE (Express Edition) which shows the following:
SQL> show user
USER is "SYS"
SQL> select tablespace_name from dba_tablespaces;
TABLESPACE_NAME
------------------------------
SYSTEM
SYSAUX
UNDOTBS1
TEMP --> temporary
USERS --> my data
Now, create a user:
SQL> create user mdp identified by pdm
2 default tablespace users
3 temporary tablespace temp
4 quota unlimited on users;
User created.
Quite a long time ago, there were two popular predefined roles named CONNECT and RESOURCE which were granted some of the most frequent privileges so people just loved to grant those roles to newly created users.
Nowadays, you shouldn't be doing that: grant only minimal set of privileges your user might need. The first one is CREATE SESSION; without it, your user won't even be able to establish a connection.
SQL> grant create session to mdp;
Grant succeeded.
Then, you'll want to create some tables so - grant it:
SQL> grant create table to mdp;
Grant succeeded.
OK, let's connect as newly created user and do something:
SQL> connect mdp/pdm#xe
Connected.
SQL> create table test (id number);
Table created.
SQL> insert into test id values (1);
1 row created.
SQL> drop table test;
Table dropped.
SQL>
Nice; I can create tables, insert/update/delete/select from them. For beginning, that's quite enough. However, when it turns out that you'd want to, for example, create a view, it won't work until you grant it that privilege:
SQL> create view v_dual as select * From dual;
create view v_dual as select * From dual
*
ERROR at line 1:
ORA-01031: insufficient privileges
SQL> connect sys#xe as sysdba
Enter password:
Connected.
SQL> grant create view to mdp;
Grant succeeded.
SQL> connect mdp/pdm#xe
Connected.
SQL> create view v_dual as select * From dual;
View created.
SQL>
And so forth; don't grant anything just because you might need it - grant it if & when you need it. Especially pay attention to system privileges which can potentially be dangerous if you don't know what you're doing.
In Oracle you can grant system privileges like
GRANT CREATE TRIGGER TO MY_USER;
But you can as well grant privileges this way
GRANT CREATE ANY TRIGGER TO MY_USER;
As system privileges are system-wide, where is the difference between the 2 statements above. Does the additional ANY-keyword grant anything else more than system? If I add a Grant ... ON SCHEMA ... it's no system privilege anymore, is it?
Assumption is that there are multiple schemas/objects in the database from different users one cannot access without these privileges.
EDIT:
SELECT *
FROM DBA_SYS_PRIVS
WHERE grantee = 'MY_USER';
returns
GRANTEE PRIVILEGE
------------ -------------
MY_USER CREATE ANY TRIGGER
MY_USER CREATE TRIGGER
(I omitted the columns ADMIN_OPTION and COMMON)
And the result is the same when querying this with MY_USER, MY_USER2 or any other user. I see no connection to a schema here. And it is also possible to only have the CREATE ANY TRIGGER-privilege.
In most cases, the trigger owner is also the owner of the table (or view) on which the trigger is based. In those cases, the table owner, with CREATE TRIGGER can create create triggers on their own table.
CREATE ANY TRIGGER allows the user to create a trigger owned by any user on any table. It is a big security hole because they can create a trigger owned by a privileged user on a table that they own or can insert into. Because they can insert into that table, they can force the trigger to execute and the trigger executes with the privileges of the trigger owner. The effect is that a user with CREATE ANY TRIGGER privilege can create and execute code as a privileged user (similar to having CREATE ANY PROCEDURE plus EXECUTE ANY PROCEDURE).
Limit to as few as people as possible and audit appropriately.
The first statements grants the right to create triggers in the schema of MY_USER. The owner will always by MY_USER.
The second statements grants the right to create triggers in ANY schema. The owner of the trigger can then be any user.
The last option is usually not wanted because it gives user MY_USERS the possibility to corrupt the data model.
How to create database link to access dba tables from another user (which has no dba rights)? I want to take back up of sys.aud$ table in another tablespace which belongs to a user, but I am unable to access it.
you dont need to create a link. You my just grant select on this table/view to any user or create view and grant select on view. eg:
connect sys/<pass> as sysdba
grant select on sys.aud$ to NON_DBA_USER;
or create view with some restrictions:
create view view_to_grant_with_rest as select * from sys.aud$ where rownum < 11;
grant select on view_to_grant_with_rest to NON_DBA_USER;
I am trying to grant access to a table from schema1 to schema2 (oracle10g).
I created a synonym on schema2:
CREATE SYNONYM schema2.table FOR schema1.table;
The synonym was created succesfully.
Then I tried to grant select on the same table:
grant select on schema1.table to schema2;
I got:
ORA-00942: table or view does not exist
This doesn't make sense to me. I was able to create the synonym but not the grant. What I am doing wrong?
I am not able to get the table from schema2:
select * from table;
ORA-00942: table or view does not exist
If I have "CREATE ANY SYNONYM| rights, I can create the synonym for the table in schema 1 in schema 2 without needing grants on the underlying objects. If I don't have rights on the schema1 table (GRANT WITH GRANT OPTION) to re-grant it to another user, then I can't also do the grant from this user.
Solution, log in as schema1 and do the grant there and then the synonym will work under schema2, or ensure that the user I AM logged in under has the rights to confer the grant on the schema1 object.
Per your comment:
Log in as schema1 and grant whichever operations you want schema2 to have on your table.
e.g)
SQL> GRANT SELECT, INSERT, UPDATE, DELETE on TABLE to SCHEMA2;
SCHEMA2 will then be able to see the table through its synonym, and be permitted those operations on it.
If SCHEMA2 is going to use this table in a view that it will then be granting select access to other schemas to use, then you need to add "WITH GRANT OPTION" to the initial grant from schema1 or schema2 will not be able to re-grant permissions on to other users.
You can create synonyms for objects that don't actually exist e.g.
create synonym flub for blib;
...so the fact that you were able to create a synonym does not mean the objects exists.