4.3 Ensure OverRide Is Disabled for the OS Root Directory - exclude AllowOverrideList

Information

The Apache 'AllowOverRide' directive and the new 'AllowOverrideList' directive allow for '.htaccess' files to be used to override much of the configuration, including authentication, handling of document types, auto generated indexes, access control, and options. When the server finds an '.htaccess' file (as specified by 'AccessFileName') it needs to know which directives declared in that file can override earlier access information. When this directive is set to 'None', then '.htaccess' files are completely ignored. In this case, the server will not even attempt to read '.htaccess' files in the filesystem. When this directive is set to 'All', then any directive which has the '.htaccess' Context is allowed in the '.htaccess' files.

Rationale:

While the functionality of 'htaccess' files is sometimes convenient, usage decentralizes the access controls and increases the risk of configurations being changed or viewed inappropriately by an unintended or rogue '.htaccess' file. Consider also that some of the more common vulnerabilities in web servers and web applications allow the web files to be viewed or to be modified, then it is wise to keep the configuration out of the web server from being placed in '.htaccess' files.

Solution

Perform the following to implement the recommended state:

1. Search the Apache configuration files ('httpd.conf' and any included configuration files) to find a root '<Directory>' element.
2. Remove any 'AllowOverrideList' directives found.
3. Add a single 'AllowOverride' directive if there is none.
4. Set the value for 'AllowOverride' to 'None'.

<Directory />
...
AllowOverride None
...
</Directory>

See Also

https://workbench.cisecurity.org/files/2381