SQL Server must allow only the ISSM (or individuals or roles appointed by the ISSM) to select which auditable events are to be audited.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-213905	SQL6-D0-000700	SV-213905r508025_rule		Medium

Description
Without the capability to restrict which roles and individuals can select which events are audited, unauthorized personnel may be able to prevent or interfere with the auditing of critical events. Suppression of auditing could permit an adversary to evade detection. Misconfigured audits can degrade the system's performance by overwhelming the audit log. Misconfigured audits may also make it more difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one.

Description

Without the capability to restrict which roles and individuals can select which events are audited, unauthorized personnel may be able to prevent or interfere with the auditing of critical events. Suppression of auditing could permit an adversary to evade detection. Misconfigured audits can degrade the system's performance by overwhelming the audit log. Misconfigured audits may also make it more difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one.

STIG	Date
MS SQL Server 2016 Database Security Technical Implementation Guide	2021-12-10

Details

Check Text ( C-15123r457863_chk )
Obtain the list of approved audit maintainers from the system documentation. Use the following query to review database roles and their membership, all of which enable the ability to create and maintain audit specifications. SELECT R.name AS role_name, RM.name AS role_member_name, RM.type_desc FROM sys.database_principals R JOIN sys.database_role_members DRM ON R.principal_id = DRM.role_principal_id JOIN sys.database_principals RM ON DRM.member_principal_id = RM.principal_id WHERE R.type = 'R' AND R.name = 'db_owner' ORDER BY role_member_name If any role memberships are not documented and authorized, this is a finding. Review the database roles and individual users that have the following permissions, all of which enable the ability to create and maintain audit definitions. ALTER ANY DATABASE AUDIT CONTROL Use the following query to determine the roles and users that have the listed permissions: SELECT PERM.permission_name, DP.name AS principal_name, DP.type_desc AS principal_type, DBRM.role_member_name FROM sys.database_permissions PERM JOIN sys.database_principals DP ON PERM.grantee_principal_id = DP.principal_id LEFT OUTER JOIN ( SELECT R.principal_id AS role_principal_id, R.name AS role_name, RM.name AS role_member_name FROM sys.database_principals R JOIN sys.database_role_members DRM ON R.principal_id = DRM.role_principal_id JOIN sys.database_principals RM ON DRM.member_principal_id = RM.principal_id WHERE R.type = 'R' ) DBRM ON DP.principal_id = DBRM.role_principal_id WHERE PERM.permission_name IN ('CONTROL','ALTER ANY DATABASE AUDIT') ORDER BY permission_name, principal_name, role_member_name If any of the roles or users returned have permissions that are not documented, or the documented audit maintainers do not have permissions, this is a finding.

Check Text ( C-15123r457863_chk )

Obtain the list of approved audit maintainers from the system documentation.

Use the following query to review database roles and their membership, all of which enable the ability to create and maintain audit specifications.

SELECT
R.name AS role_name,
RM.name AS role_member_name,
RM.type_desc
FROM sys.database_principals R
JOIN sys.database_role_members DRM ON
R.principal_id = DRM.role_principal_id
JOIN sys.database_principals RM ON
DRM.member_principal_id = RM.principal_id
WHERE R.type = 'R'
AND R.name = 'db_owner'
ORDER BY
role_member_name

If any role memberships are not documented and authorized, this is a finding.

Review the database roles and individual users that have the following permissions, all of which enable the ability to create and maintain audit definitions.

ALTER ANY DATABASE AUDIT
CONTROL

Use the following query to determine the roles and users that have the listed permissions:

SELECT
PERM.permission_name,
DP.name AS principal_name,
DP.type_desc AS principal_type,
DBRM.role_member_name
FROM sys.database_permissions PERM
JOIN sys.database_principals DP ON PERM.grantee_principal_id = DP.principal_id
LEFT OUTER JOIN (
SELECT
R.principal_id AS role_principal_id,
R.name AS role_name,
RM.name AS role_member_name
FROM sys.database_principals R
JOIN sys.database_role_members DRM ON R.principal_id = DRM.role_principal_id
JOIN sys.database_principals RM ON DRM.member_principal_id = RM.principal_id
WHERE R.type = 'R'
) DBRM ON DP.principal_id = DBRM.role_principal_id
WHERE PERM.permission_name IN ('CONTROL','ALTER ANY DATABASE AUDIT')
ORDER BY
permission_name,
principal_name,
role_member_name

If any of the roles or users returned have permissions that are not documented, or the documented audit maintainers do not have permissions, this is a finding.

Fix Text (F-15121r313148_fix)
Create a database role specifically for audit maintainers, and give it permission to maintain audits, without granting it unnecessary permissions (The role name used here is an example; other names may be used.): CREATE ROLE DATABASE_AUDIT_MAINTAINERS; GO GRANT ALTER ANY DATABASE AUDIT TO DATABASE_AUDIT_MAINTAINERS; GO Use REVOKE and/or DENY and/or ALTER ROLE ... DROP MEMBER ... statements to remove the ALTER ANY DATABASE AUDIT permission from all users. Then, for each authorized database user, run the statement: ALTER ROLE DATABASE_AUDIT_MAINTAINERS ADD MEMBER; GO Use REVOKE and/or DENY and/or ALTER SERVER ROLE ... DROP MEMBER ... statements to remove CONTROL DATABASE permission from logins that do not need it.

Fix Text (F-15121r313148_fix)

Create a database role specifically for audit maintainers, and give it permission to maintain audits, without granting it unnecessary permissions (The role name used here is an example; other names may be used.):

CREATE ROLE DATABASE_AUDIT_MAINTAINERS;
GO

GRANT ALTER ANY DATABASE AUDIT TO DATABASE_AUDIT_MAINTAINERS;
GO

Use REVOKE and/or DENY and/or ALTER ROLE ... DROP MEMBER ... statements to remove the ALTER ANY DATABASE AUDIT permission from all users. Then, for each authorized database user, run the statement:

ALTER ROLE DATABASE_AUDIT_MAINTAINERS ADD MEMBER;
GO

Use REVOKE and/or DENY and/or ALTER SERVER ROLE ... DROP MEMBER ... statements to remove CONTROL DATABASE permission from logins that do not need it.