I want to create a user that will have only read permissions
That it will be able to run SELECT queries but will not be able to run UPDATE,INSERT... or modify the DB.
I read that USAGE means - no permissions, what can it do?
Will a user with USAGE permissions be able to modify the DB?
In phpMyadmin you set priviliges according to your wishes. This meaning:
If you only wan't the user to be able to run SELECT queries, Thats what you select. The user will then not beable to edit your data in any way.
Hope this helps.
The best way to learn the capabilities of an account is to test it, try to create a test table and log in with that user, try also to execute the writing commands on it and you'll see by yourself if he can write or not.
https://dev.mysql.com/doc/refman/5.1/en/privileges-provided.html#priv_usage
The USAGE privilege specifier stands for “no privileges.” It is used at the global level with GRANT to modify account attributes such as resource limits or SSL characteristics without affecting existing account privileges.
So no, a user with only USAGE will not be able to see or create other databases. They can connect, see information_schema, get STATUS, and very little else.
Anyway, you've mentioned phpMyAdmin which doesn't provide USAGE as a checkbox in the permissions area; creating a user with no other options selected gives USAGE privileges here. Select anything further you wish to allow from the checkboxes provided.
Related
So we've got a MYSQL database with very sensitive information and we want to prevent it from being exported by a developer/admin who has access to it, while still allowing them to access database while working on their duties.
In simple terms we want to prohibit mass select on specific tables.
Ideally it would be an option to disable mass select, something like limit 0, 1 enforcement for all SELECT queries on specific tables. Is it possible to configure MYSQL like that? Any other ideas how to prevent database from being exported?
Any solution I can think of when someone needs to access your production data within MySQL and you want to apply the principle of least privilege leads to separation of users and to the page on GRANT command in MySQL documentation.
But as I said in a comment to you question, it is much easier to develop a procedure to generate an impersonated sample of your data, so that your developers would not have access to the production data.
I am new to MySQL and I ran a Nessus scan on one my Servers and encountered a security finding which has a workaround to Restrict access to user-defined functions. Can someone help me please?
Update
The workaround is to Restrict access to create user-defined functions on the server
This should work.
You can read more here http://dev.mysql.com/doc/refman/5.0/en/revoke.html
REVOKE EXECUTE ON FUNCTION mydb.myfunc FROM 'someuser'#'somehost';
However,
In my opinion it's better to grant certain users specific permissions rather making everything accessible and revoking perms from users. (It depends on the application)
Learn how to GRANT permission only to specific user ids and hosts:
http://dev.mysql.com/doc/refman/5.1/en/grant.html
I am looking for an example or information on row level security for PHP and MySQL. I have done the basic google reasearch, I have read all the posts / articles about using views and adding fields to table to specify what user has the right to view the object. Those example are fairly simple and would require lots of configuration / maintenance.
Here are a few real life examples of what i am looking for:
Clients data, allow to configurer what user or user group can view all or parts of the client file. This must be persistent for all the application features including reports and dashboards.
Employee files, give access to immediate supervisor and HR to an employee file without having to reconfigurer the access rights when supervisors change.
I think this should be handled directly from the database layer, but could also be applied to other resources for examples, uploaded documents.
I'm hinting to some sort of "filter" that I could pass my data into so it could be filtered.
Any interesting links to articles or frameworks that have implemented this with success would be greatly appreciated.
Thanks.
You would need to use MariaDB to do this, as MySQL doesn't do ROLEs, though you might be able to use GRANT PROXY to accomplish what you want in MySQL.
I think that different "tenants", i.e. paying customers, should be in different databases to avoid leakage. You can use scripting to automate this.
But if you want intra-company row-level security, you can accomplish this with an extra column per table and some views and triggers.
create a table with an owner column. Use an insert trigger to set owner to the current user. REVOKE all privileges on the table.
create a view WITH CHECK OPTION on that table that checks that current user is in a role that matches the owner. GRANT all privileges on the view.
Example:
create user `pointyHead`;
create user `dilbert`;
create role `manager`;
create role `minion`;
grant manager to pointyHead;
grant minion to dilbert;
grant minion to manager;
Not sure if there is a function to check if user is in role, but you can always use information_schema.applicable_roles.
You can use column-level grants to give different column permissions to different users. http://dev.mysql.com/doc/refman/5.5/en/grant.html#grant-column-privileges .
Suppose you're writing a simple database web application using Ruby and MySQL. Access to the database is controlled by Ruby code. The user name that the Ruby code uses to access the data is the only regular user on the database. Does it make sense for that user to be "root"? Or is there any extra security in creating a second user just for the application?
Simple, consider the root as the main user, who can do everything (by default).
If he wants to dump the whole database, he can, if he wants to create some data to create (for example) fake account to overpass your bank system, he can.
So if your code is not enough secure (and this is quite often usually), you have strong security issue.
Usually, "a basic" security (really basic), should looks like that :
create a simple user, give him (with GRANTS) the right to SELECT, INSERT, UPDATE and DELETE on a specific database.
create another user who can SELECT and lock tables and SHOW VIEWS to perform dump (database save).
On a more "complex" system, you should create many users, depending of what they should access, this is for simple reason : if somebody got a SQL injection access, if the user can only access to a single view (for example), and not the whole database, this is a security issue but not the baddest one...
Also view are often used for that...
And finally don't forget triggers if you want (for example a log table), to disable insert or update or delete on a table, for everybody (except somebody who can destroy trigger of course) :
Use a trigger to stop an insert or update
Besides editing or deleting all data in your database, the root user also have the FILE privilege which gives access to:
LOAD DATA INFILE which can be used to read any file on the server machine.
LOAD DATA LOCAL INFILE which can read files on the client machine (the web server machine).
SELECT ... INTO OUTFILE which can create files on the server machine.
This is why your application should have only the privileges it needs, and this is also the reason your MySQL server daemon should be run as a non-privileged user on the server machine.
See also General Security Issues in the manual.
If everybody/thing is root, you lose auditability, you lose the ability to restrict the app to stop attacks (i.e. your app doesn't need this segment of sensitive information, seal it away from its user). If somebody compromises the app, you can suspend the account etc.
I would not make a user "root".
I'd create a separate username and password just for that application and GRANT it only the permissions required to do its job.
I would create a new user, giving it only the permissions it needs (SELECT, UPDATE, INSERT and DELETE usually do the trick). Like that, you limit the ability for the code to be manipulated in an unintended way.
"root", or generally speaking, users with Super User privileges, can change passwords, delete accounts, and therefore prevent you from accessing your own database.
If you server hosts only one application, then you may not need to create several lesser privileged accounts. However, it is common practice to create at least one user for each application, so that if one application gets compromised, other applications (and underlying data) may not be.
The datasource used by my web application connects using the ROOT user. The ROOT user has all privileges assigned.
My concerns are:
1) Should I be using this user (and is it ok / secure) or should I create another user with a more restricted set of rights
2) If I do use another user, how do I cater for all my procs that begin with:
CREATE DEFINER=`root`#`%` PROCEDURE `Blah`()
3) Is it a bad idea removing privileges from the ROOT user. For example, if I remove the "DROP" privilege, will I still be able to DROP objects when logging in via the Admin or Query Browser. MY guess would be no and that I shouldn't mess with the privileges.
Any documentation / links / info regarding this would be appreciated. Thanks
You should absolutely use a restricted user to access the database as much as possible.
There are privileges that allow your users to access procedures. I'm not that familiar with it but here's the official documentation: http://dev.mysql.com/doc/refman/5.0/en/create-procedure.html
Don't mess with root's privileges :)
No, your application should not connect using the root user. You should create and configure a user that has the permissions required by the application and no more.
I usually go with at least three users:
Root can do everything; changing root's permissions is a recipe for disaster (unless you know exactly what you are doing)
The application has its own user, and this user has very restrictive permissions - usually just SELECT, UPDATE, INSERT, DELETE on the tables it needs. In any case, no permissions that would allow schema modifications (CREATE / ALTER TABLE and such).
A special user which can access the application's database, but nothing else. This user is used for maintenance tasks such as schema upgrades, but not for the application itself.
It's a bad idea to use the root user for any task. You can see it like the system-user: only the system should use it, when it needs it, to do everything.
Create a new user and give it only access and priviledges to do what it should do. This is called the principle of least privilege.
In this case, procedures are part of what a certain user, module or part of a program should do in normal circumstances. Hence, the user you create owns (DEFINER) that procedure. You should remove the procedure from the root user and add it to your newly created user. If it's impossible to remove from the root user: then so be it! However:
If a user want to access the procedure, give (GRANT) them access to it. In the case the root user still owns the procedure, any other user still can be granted to use the procedure.
The root user is, as I already mentioned, the system user. If you drop priviledges then any program or user using the root can't do what is expected (being the system-user capable of doing everything), and this cripples your system.
Think about this: how would you add a new database, if you dropped the "ADD DATABASE" privilege from the root user?