V-276306

Discussion

If Azure SQL Managed Instance provides too much information in error logs and administrative messages to the screen, this could lead to compromise. The structure and content of error messages must be carefully considered by the organization and development team. The extent to which the information system is able to identify and handle error conditions is guided by organizational policy and operational requirements. Some default database management system (DBMS) error messages can contain information that could aid an attacker in, among other things, identifying the database type, host address, or state of the database. Custom errors may contain sensitive customer information. It is important that detailed error messages be visible only to those who are authorized to view them; that general users receive only generalized acknowledgment that errors have occurred; and that these generalized messages appear only when relevant to the user's task. For example, a message along the lines of, "An error has occurred. Unable to save your changes. If this problem persists, please contact your help desk." would be relevant. A message such as "Warning: your transaction generated a large number of page splits" would likely not be relevant. "ABGQ is not a valid widget code." would be appropriate; but "The INSERT statement conflicted with the FOREIGN KEY constraint 'WidgetTransactionFK'. The conflict occurred in database 'DB7', table 'dbo.WidgetMaster', column 'WidgetCode''' would not, as it reveals too much about the database structure.

Check Content

Error messages within applications, custom database code (stored procedures, triggers) must be enforced by guidelines and code reviews practices.  
 
Azure SQL Managed Instance generates certain system events and user-defined events to the Azure SQL Managed Instance error log. The Azure SQL Managed Instance error log can be viewed using SQL Server Management Studio GUI. All users granted the security admin or sysadmin level of permission are able to view the logs. Review the users returned in the following script: 
 
USE master 
GO
SELECT Name 
FROM syslogins 
WHERE (sysadmin = 1 or securityadmin = 1) 
and hasaccess = 1; 
 
If any nonauthorized users have access to the Azure SQL Managed Instance Error Log in SQL Server Management Studio, this is a finding.