Title

The IIS 8.5 website must be configured to limit the size of web requests. (Cat II impact)

Discussion

By setting limits on web requests, it ensures availability of web services and mitigates the risk of buffer overflow type attacks. The maxAllowedContentLength Request Filter limits the number of bytes the server will accept in a request.

Check Content

Follow the procedures below for each site hosted on the IIS 8.5 web server: Open the IIS 8.5 Manager. Click on the site name. Double-click the "Request Filtering" icon. Click “Edit Feature Settings” in the "Actions" pane. If the "maxAllowedContentLength" value is not explicitly set to "30000000" or less or a length documented and approved by the ISSO, this is a finding.

Fix Text

Follow the procedures below for each site hosted on the IIS 8.5 web server: Open the IIS 8.5 Manager. Click the site name under review. Double-click the "Request Filtering" icon. Click “Edit Feature Settings” in the "Actions" pane. Set the "maxAllowedContentLength" value to "30000000" or less.

Additional Identifiers

Rule ID: SV-214465r879650_rule

Vulnerability ID: V-214465

Group Title: SRG-APP-000246-WSR-000149

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.