SQL Server must enforce access control policies to restrict the Alter any connection permission to only authorized roles.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-41297	SQL2-00-002900	SV-53779r3_rule		Medium

Description
The concept of least privilege must be applied to SQL Server processes, ensuring that the processes operate at privilege levels no higher than necessary to accomplish required organizational missions and/or functions. Organizations consider the creation of additional processes, roles, and SQL Server accounts as necessary to achieve least privilege. Organizations also apply least privilege concepts to the design, development, implementation, and operations of SQL Server and the OS. Unauthorized access to sensitive data or SQL Server control may compromise the confidentiality of personnel privacy, threaten national security, compromise a variety of other sensitive operations, or lead to a loss of system control. Access controls are best managed by defining requirements based on distinct job functions and assigning access based on the job function assigned to the individual user. SQL Server's 'Alter any connection' permission is a high server-level privilege that must only be granted to individual administration accounts through roles. If the 'Alter any connection' permission is granted to roles that are unauthorized to have this privilege, then this access must be removed. Additionally, the permission must not be denied to a role, because that could disable a user's legitimate access via another role. The fix for this vulnerability specifies the use of REVOKE. Be aware that revoking a permission that is currently denied to a role or user does not necessarily disable the permission. If the user or role can inherent the permission from another role, revoking the denied permission from the user or the first role can effectively enable the inherited permission.

Description

The concept of least privilege must be applied to SQL Server processes, ensuring that the processes operate at privilege levels no higher than necessary to accomplish required organizational missions and/or functions. Organizations consider the creation of additional processes, roles, and SQL Server accounts as necessary to achieve least privilege. Organizations also apply least privilege concepts to the design, development, implementation, and operations of SQL Server and the OS. Unauthorized access to sensitive data or SQL Server control may compromise the confidentiality of personnel privacy, threaten national security, compromise a variety of other sensitive operations, or lead to a loss of system control. Access controls are best managed by defining requirements based on distinct job functions and assigning access based on the job function assigned to the individual user. SQL Server's 'Alter any connection' permission is a high server-level privilege that must only be granted to individual administration accounts through roles. If the 'Alter any connection' permission is granted to roles that are unauthorized to have this privilege, then this access must be removed. Additionally, the permission must not be denied to a role, because that could disable a user's legitimate access via another role. The fix for this vulnerability specifies the use of REVOKE. Be aware that revoking a permission that is currently denied to a role or user does not necessarily disable the permission. If the user or role can inherent the permission from another role, revoking the denied permission from the user or the first role can effectively enable the inherited permission.

STIG	Date
Microsoft SQL Server 2012 Database Instance Security Technical Implementation Guide	2017-04-03

Details

Check Text ( C-47865r3_chk )
Obtain the list of roles that are authorized for the SQL Server 'Alter any connection' permission and what 'Grant', 'Grant With', and/or 'Deny' privilege is authorized. Obtain the list of roles with that permission by running the following query: SELECT who.name AS [Principal Name], who.type_desc AS [Principal Type], who.is_disabled AS [Principal Is Disabled], what.state_desc AS [Permission State], what.permission_name AS [Permission Name] FROM sys.server_permissions what INNER JOIN sys.server_principals who ON who.principal_id = what.grantee_principal_id WHERE what.permission_name = 'Alter any connection' AND who.type_desc = 'SERVER_ROLE' ORDER BY who.name ; GO If any role has 'Grant', 'With Grant' or 'Deny' privileges on this permission and users with that role are not authorized to have the permission, this is a finding.

Check Text ( C-47865r3_chk )

Obtain the list of roles that are authorized for the SQL Server 'Alter any connection' permission and what 'Grant', 'Grant With', and/or 'Deny' privilege is authorized. Obtain the list of roles with that permission by running the following query:

SELECT
who.name AS [Principal Name],
who.type_desc AS [Principal Type],
who.is_disabled AS [Principal Is Disabled],
what.state_desc AS [Permission State],
what.permission_name AS [Permission Name]
FROM
sys.server_permissions what
INNER JOIN sys.server_principals who
ON who.principal_id = what.grantee_principal_id
WHERE
what.permission_name = 'Alter any connection'
AND who.type_desc = 'SERVER_ROLE'
ORDER BY
who.name
;
GO

If any role has 'Grant', 'With Grant' or 'Deny' privileges on this permission and users with that role are not authorized to have the permission, this is a finding.

Fix Text (F-46688r1_fix)
Remove the 'Alter any connection' permission access from the role that is not authorized by executing the following query: REVOKE Alter any connection TO <'role name'>