Useful SQL Scripts for Auditing Logical Access
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Overview
When you have to scope a database into your engagement, you may be curious how to best extract the information from the database. While there are numerous different methods to extract this type of information, I'm going to show an example of how to gather all users and privileges from three main database types: Oracle, Microsoft SQL, and MySQL.
Oracle
You can use the following SQL script to see all users and their privileges in an Oracle database:
SELECT
grantee AS "User",
privilege AS "Privilege"
FROM
dba_sys_privs
WHERE
grantee IN (SELECT DISTINCT grantee FROM dba_sys_privs)
UNION ALL
SELECT
grantee AS "User",
privilege AS "Privilege"
FROM
dba_tab_privs
WHERE
grantee IN (SELECT DISTINCT grantee FROM dba_tab_privs);
This script queries the dba_sys_privs
and dba_tab_privs
views to retrieve system and table-level privileges respectively. It then combines the results using UNION ALL
to show all users and their associated privileges. Please note that this method does not extract information from the dba_role_privs
table - use the method below for that data.
Please note that you might need appropriate privileges (e.g., DBA privileges) to access these views, and you should exercise caution when querying system tables in a production Oracle database.
Alternative Oracle Query
You can also extract each table's information separately and perform processing outside the database to explore and determine the information necessary for the audit:
SELECT * FROM sys.dba_role_privs;
SELECT * FROM sys.dba_sys_privs;
SELECT * FROM sys.dba_tab_privs;
SELECT * FROM sys.dba_users;
Microsoft SQL
You can use the following SQL script to see all users and their privileges in a Microsoft SQL Server database (source):
/*
Security Audit Report
1) List all access provisioned to a sql user or windows user/group directly
2) List all access provisioned to a sql user or windows user/group through a database or application role
3) List all access provisioned to the public role
Columns Returned:
UserName : SQL or Windows/Active Directory user account. This could also be an Active Directory group.
UserType : Value will be either 'SQL User' or 'Windows User'. This reflects the type of user defined for the
SQL Server user account.
DatabaseUserName: Name of the associated user as defined in the database user account. The database user may not be the
same as the server user.
Role : The role name. This will be null if the associated permissions to the object are defined at directly
on the user account, otherwise this will be the name of the role that the user is a member of.
PermissionType : Type of permissions the user/role has on an object. Examples could include CONNECT, EXECUTE, SELECT
DELETE, INSERT, ALTER, CONTROL, TAKE OWNERSHIP, VIEW DEFINITION, etc.
This value may not be populated for all roles. Some built in roles have implicit permission
definitions.
PermissionState : Reflects the state of the permission type, examples could include GRANT, DENY, etc.
This value may not be populated for all roles. Some built in roles have implicit permission
definitions.
ObjectType : Type of object the user/role is assigned permissions on. Examples could include USER_TABLE,
SQL_SCALAR_FUNCTION, SQL_INLINE_TABLE_VALUED_FUNCTION, SQL_STORED_PROCEDURE, VIEW, etc.
This value may not be populated for all roles. Some built in roles have implicit permission
definitions.
ObjectName : Name of the object that the user/role is assigned permissions on.
This value may not be populated for all roles. Some built in roles have implicit permission
definitions.
ColumnName : Name of the column of the object that the user/role is assigned permissions on. This value
is only populated if the object is a table, view or a table value function.
*/
--List all access provisioned to a sql user or windows user/group directly
SELECT
[UserName] = CASE princ.[type]
WHEN 'S' THEN princ.[name]
WHEN 'U' THEN ulogin.[name] COLLATE Latin1_General_CI_AI
END,
[UserType] = CASE princ.[type]
WHEN 'S' THEN 'SQL User'
WHEN 'U' THEN 'Windows User'
END,
[DatabaseUserName] = princ.[name],
[Role] = null,
[PermissionType] = perm.[permission_name],
[PermissionState] = perm.[state_desc],
[ObjectType] = obj.type_desc,--perm.[class_desc],
[ObjectName] = OBJECT_NAME(perm.major_id),
[ColumnName] = col.[name]
FROM
--database user
sys.database_principals princ
LEFT JOIN
--Login accounts
sys.login_token ulogin on princ.[sid] = ulogin.[sid]
LEFT JOIN
--Permissions
sys.database_permissions perm ON perm.[grantee_principal_id] = princ.[principal_id]
LEFT JOIN
--Table columns
sys.columns col ON col.[object_id] = perm.major_id
AND col.[column_id] = perm.[minor_id]
LEFT JOIN
sys.objects obj ON perm.[major_id] = obj.[object_id]
WHERE
princ.[type] in ('S','U')
UNION
--List all access provisioned to a sql user or windows user/group through a database or application role
SELECT
[UserName] = CASE memberprinc.[type]
WHEN 'S' THEN memberprinc.[name]
WHEN 'U' THEN ulogin.[name] COLLATE Latin1_General_CI_AI
END,
[UserType] = CASE memberprinc.[type]
WHEN 'S' THEN 'SQL User'
WHEN 'U' THEN 'Windows User'
END,
[DatabaseUserName] = memberprinc.[name],
[Role] = roleprinc.[name],
[PermissionType] = perm.[permission_name],
[PermissionState] = perm.[state_desc],
[ObjectType] = obj.type_desc,--perm.[class_desc],
[ObjectName] = OBJECT_NAME(perm.major_id),
[ColumnName] = col.[name]
FROM
--Role/member associations
sys.database_role_members members
JOIN
--Roles
sys.database_principals roleprinc ON roleprinc.[principal_id] = members.[role_principal_id]
JOIN
--Role members (database users)
sys.database_principals memberprinc ON memberprinc.[principal_id] = members.[member_principal_id]
LEFT JOIN
--Login accounts
sys.login_token ulogin on memberprinc.[sid] = ulogin.[sid]
LEFT JOIN
--Permissions
sys.database_permissions perm ON perm.[grantee_principal_id] = roleprinc.[principal_id]
LEFT JOIN
--Table columns
sys.columns col on col.[object_id] = perm.major_id
AND col.[column_id] = perm.[minor_id]
LEFT JOIN
sys.objects obj ON perm.[major_id] = obj.[object_id]
UNION
--List all access provisioned to the public role, which everyone gets by default
SELECT
[UserName] = '{All Users}',
[UserType] = '{All Users}',
[DatabaseUserName] = '{All Users}',
[Role] = roleprinc.[name],
[PermissionType] = perm.[permission_name],
[PermissionState] = perm.[state_desc],
[ObjectType] = obj.type_desc,--perm.[class_desc],
[ObjectName] = OBJECT_NAME(perm.major_id),
[ColumnName] = col.[name]
FROM
--Roles
sys.database_principals roleprinc
LEFT JOIN
--Role permissions
sys.database_permissions perm ON perm.[grantee_principal_id] = roleprinc.[principal_id]
LEFT JOIN
--Table columns
sys.columns col on col.[object_id] = perm.major_id
AND col.[column_id] = perm.[minor_id]
JOIN
--All objects
sys.objects obj ON obj.[object_id] = perm.[major_id]
WHERE
--Only roles
roleprinc.[type] = 'R' AND
--Only public role
roleprinc.[name] = 'public' AND
--Only objects of ours, not the MS objects
obj.is_ms_shipped = 0
ORDER BY
princ.[Name],
OBJECT_NAME(perm.major_id),
col.[name],
perm.[permission_name],
perm.[state_desc],
obj.type_desc--perm.[class_desc]
MySQL
You can use the following SQL script to see all users and their privileges in a MySQL database:
mysql -u root -p
Find all users and hosts with access to the database:
SELECT * FROM information_schema.user_privileges;
This script retrieves user information and their associated database-level privileges from the information_schema.user_privileges
table in MySQL. It lists various privileges such as SELECT, INSERT, UPDATE, DELETE, CREATE, and more for each user and database combination.
Please note that you may need appropriate privileges (e.g., SELECT
privileges on information_schema.user_privileges
) to access this information in a MySQL database. Additionally, some privileges like GRANT OPTION, EXECUTE, EVENT, and TRIGGER may not be relevant for all users and databases.
Alternative MySQL Query
You can also grab individual sets of data from MySQL if you prefer to join them after extraction. I have marked the queries below with SELECT ...
and excluded most WHERE
clauses for brevity. You should determine the relevant privileges in-scope and query for those privileges to reduce the length of time to query.
-- Global Permissions
SELECT ... FROM mysql.user;
-- Database Permissions
SELECT ... FROM mysql.db
WHERE db = @db_name;
-- Table Permissions
SELECT ... FROM mysql.tables
WHERE db = @db_name;
-- Column Permissions
SELECT ... FROM mysql.columns_priv
WHERE db = @db_name;
-- Password Configuration
SHOW GLOBAL VARIABLES LIKE 'validate_password%';
SHOW VARIABLES LIKE 'validate_password%';