Title

Mappings to unused and vulnerable scripts on the IIS 8.5 website must be removed. (Cat II impact)

Discussion

IIS 8.5 will either allow or deny script execution based on file extension. The ability to control script execution is controlled through two features with IIS 8.5, “Request Filtering” and "Handler Mappings". For "Request Filtering", the ISSO must document and approve all allowable file extensions the website allows (white list) and denies (black list) by the website. The white list and black list will be compared to the "Request Filtering" in IIS 8. "Request Filtering" at the site level take precedence over "Request Filtering" at the server level.

Check Content

Note: If the server being reviewed is hosting SharePoint, this is Not Applicable. For Request Filtering, the ISSO must document and approve all allowable scripts the website allows (white list) and denies (black list). The white list and black list will be compared to the Request Filtering in IIS 8.5. Open the IIS 8.5 Manager. Click the site name under review. Double-click "Request Filtering". If any script file extensions from the black list are enabled, this is a finding.

Fix Text

Open the IIS 8.5 Manager. Click the site name under review. Double-click "Request Filtering". Deny any script file extensions listed on the black list. Select "Apply" from the "Actions" pane.

Additional Identifiers

Rule ID: SV-214455r903087_rule

Vulnerability ID: V-214455

Group Title: SRG-APP-000141-WSR-000082

Expert Comments

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