Microsoft IIS .IDA ISAPI Filter Enabled

info Nessus Plugin ID 10695
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Indexing Service filter is enabled on the remote Web server.


The IIS server appears to have the .IDA ISAPI filter mapped.

At least one remote vulnerability has been discovered for the .IDA (indexing service) filter. This is detailed in Microsoft Advisory MS01-033, and gives remote SYSTEM level access to the web server.

It is recommended that even if you have patched this vulnerability that you unmap the .IDA extension, and any other unused ISAPI extensions if they are not required for the operation of your site.


To unmap the .IDA extension:
1.Open Internet Services Manager. 2.Right-click the Web server choose Properties from the context menu. 3.Master Properties 4.Select WWW Service -> Edit -> HomeDirectory -> Configuration 5.Remove the reference to .ida from the list.

In addition, you may wish to download and install URLSCAN from the Microsoft Technet website. URLSCAN, by default, blocks all .ida requests to the IIS server.

Plugin Details

Severity: Info

ID: 10695

File Name: iis_ida_isapi.nasl

Version: 1.37

Type: remote

Family: Web Servers

Published: 6/19/2001

Updated: 6/12/2020

Dependencies: find_service1.nasl, no404.nasl, http_version.nasl, www_fingerprinting_hmap.nasl

Vulnerability Information

CPE: cpe:/a:microsoft:iis