Access to xp_cmdshell must be disabled, unless specifically required and approved.

From MS SQL Server 2016 Instance Security Technical Implementation Guide

Part of SRG-APP-000141-DB-000093

Associated with: CCI-000381

SV-93883r1_rule Access to xp_cmdshell must be disabled, unless specifically required and approved.

Vulnerability discussion

Information systems are capable of providing a wide variety of functions and services. Some of the functions and services, provided by default, may not be necessary to support essential organizational operations (e.g., key missions, functions). It is detrimental for applications to provide, or install by default, functionality exceeding requirements or mission objectives. Applications must adhere to the principles of least functionality by providing only essential capabilities. SQL Server may spawn additional external processes to execute procedures that are defined in the SQL Server but stored in external host files (external procedures). The spawned process used to execute the external procedure may operate within a different OS security context than SQL Server and provide unauthorized access to the host system. The xp_cmdshell extended stored procedure allows execution of host executables outside the controls of database access permissions. This access may be exploited by malicious users who have compromised the integrity of the SQL Server database process to control the host operating system to perpetrate additional malicious activity.

Check content

The xp_cmdshell extended stored procedure allows execution of host executables outside the controls of database access permissions. This access may be exploited by malicious users who have compromised the integrity of the SQL Server database process to control the host operating system to perpetrate additional malicious activity. To determine if xp_cmdshell is enabled, execute the following commands: EXEC SP_CONFIGURE 'show advanced options', '1'; RECONFIGURE WITH OVERRIDE; EXEC SP_CONFIGURE 'xp_cmdshell'; If the value of "config_value" is "0", this is not a finding. Review the system documentation to determine whether the use of "xp_cmdshell" is required and approved. If it is not approved, this is a finding.

Fix text

Disable use of or remove any external application executable object definitions that are not authorized. To disable the use of xp_cmdshell, from the query prompt:  EXEC sp_configure 'show advanced options', 1;  GO  RECONFIGURE;  GO  EXEC sp_configure 'xp_cmdshell', 0;  GO  RECONFIGURE;  GO??

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.

Powered by sagemincer