TMA-IIS-3.2

Ensure 'debug' is turned off

LowLevel 2Automatediis

Description

Developers often enable the debug mode during active ASP.NET development so that they do not have to continually clear their browsers cache every time they make a change to a resource handler. The problem would arise from this being left "on" or set to "true". Compilation debug output is displayed to the end user, allowing malicious persons to obtain detailed information about applications. compilation debug must be false in the root web.config and every site. PowerShell 5.1 with the WebAdministration module; run elevated.

How it is checked

Audit method: Shell command

shell

Import-Module WebAdministration -ErrorAction Stop; $paths = @('MACHINE/WEBROOT') + @(Get-Website | ForEach-Object { "IIS:\Sites\$($_.Name)" }); $bad = @($paths | Where-Object { $c = Get-WebConfiguration -Filter 'system.web/compilation' -PSPath $_; $c.debug -ne $false }); if ($bad.Count -eq 0) { 'compliant' } else { 'noncompliant' }

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Set-WebConfigurationProperty -PSPath 'MACHINE/WEBROOT/APPHOST/<site>' -Filter system.web/compilation -Name debug -Value False

Properties

Operating systems: Any
Tags: iisaspnet
Reference: CIS Microsoft IIS 10 Benchmark v1.2.1 - 3.2 Ensure 'debug' is turned off

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target iis --level 2