Title

The IIS 10.0 website must be configured to limit the maxURL. (Cat II impact)

Discussion

Request filtering replaces URLScan in IIS, enabling administrators to create a more granular rule set with which to allow or reject inbound web content. By setting limits on web requests, it helps to ensure availability of web services and may also help mitigate the risk of buffer overflow type attacks. The MaxURL Request Filter limits the number of bytes the server will accept in a URL.

Check Content

Follow the procedures below for each site hosted on the IIS 10.0 web server: Open the IIS 10.0 Manager. Click on the site name. Double-click the "Request Filtering" icon. Click "Edit Feature Settings" in the "Actions" pane. If the "maxUrl" value is not set to "4096" or less, this is a finding.

Fix Text

Follow the procedures below for each site hosted on the IIS 10.0 web server: Click the site name under review. Double-click the "Request Filtering" icon. Click "Edit Feature Settings" in the "Actions" pane. Set the "maxURL" value to "4096" or less.

Additional Identifiers

Rule ID: SV-218753r879650_rule

Vulnerability ID: V-218753

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.