Execution of software modules (to include functions and trigger procedures) with elevated privileges must be restricted to necessary cases only.
An XCCDF Rule
Description
<VulnDiscussion>In certain situations, to provide required functionality, PostgreSQL needs to execute internal logic (stored procedures, functions, triggers, etc.) and/or external code modules with elevated privileges. However, if the privileges required for execution are at a higher level than the privileges assigned to organizational users invoking the functionality applications/programs, those users are indirectly provided with greater privileges than assigned by organizations. Privilege elevation must be utilized only where necessary and protected from misuse. This calls for inspection of application source code, which will require collaboration with the application developers. It is recognized that in many cases, the database administrator (DBA) is organizationally separate from the application developers, and may have limited, if any, access to source code. Nevertheless, protections of this type are so important to the secure operation of databases that they must not be ignored. At a minimum, the DBA must attempt to obtain assurances from the development organization that this issue has been addressed, and must document what has been discovered.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-233543r879719_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Determine where, when, how, and by what principals/subjects elevated privilege is needed.
To change a SECURITY DEFINER function to SECURITY INVOKER, as the database administrator (shown here as "postgres"), run the following SQL:
$ sudo su - postgres
$ psql -c "ALTER FUNCTION <function_name> SECURITY INVOKER"