.NET Getting Started with ASM

You can monitor application security for .NET apps running in Docker, Kubernetes, AWS ECS, and AWS Fargate.

In general, setting up Application Security Management (ASM) involves:

  1. Identifying services that are vulnerable or are under attack, which would most benefit from ASM. Find them on the Security tab of your Service Catalog.
  2. Updating to the latest Datadog library (the most recent APM tracing library).
  3. Enabling the library to collect the application security data from the services and send it to Datadog.
  4. Triggering security signals in your application and seeing how Datadog displays the resulting information.

Prerequisites

  • The Datadog Agent is installed and configured for your application’s operating system or container, cloud, or virtual environment.
  • Datadog APM is configured for your application or service, and traces are being received by Datadog.
Beta: 1-Click Enablement
If your service is running with an Agent with Remote Configuration enabled and a tracing library version that supports it, hover over the Not Enabled indicator in the ASM Status column and click Enable ASM. There's no need to re-launch the service with the DD_APPSEC_ENABLED=true or --enable-appsec flags.

Get started

  1. Update your Datadog .NET library to at least version 2.2.0 (at least version 2.16.0 for Risk Management vulnerability detection features) for your target operating system architecture.

    For information about which language and framework versions are supported by the library, see Compatibility.

  2. Enable ASM by setting the DD_APPSEC_ENABLED environment variable to true. For example, on Windows self-hosted, run the following PowerShell snippet as part of your application start up script:

    $target=[System.EnvironmentVariableTarget]::Process
    [System.Environment]::SetEnvironmentVariable("DD_APPSEC_ENABLED","true",$target)
    

    Or one of the following methods, depending on where your application runs:

    In a Windows console:

    rem Set environment variables
    SET CORECLR_ENABLE_PROFILING=1
    SET CORECLR_PROFILER={846F5F1C-F9AE-4B07-969E-05C26BC060D8}
    SET DD_APPSEC_ENABLED=true
    
    rem Start application
    dotnet.exe example.dll
    

    Run the following PowerShell command as administrator to configure the necessary environment variables in the registry HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment and restart IIS.

    $target=[System.EnvironmentVariableTarget]::Machine
    [System.Environment]::SetEnvironmentVariable("DD_APPSEC_ENABLED","true",$target)
    net stop was /y
    net start w3svc
    

    Or, for IIS services exclusively, on WAS and W3SVC with Powershell as an administrator, run:

    $appsecPart = "DD_APPSEC_ENABLED=true"
    [string[]] $defaultvariable = @("CORECLR_ENABLE_PROFILING=1", "CORECLR_PROFILER={846F5F1C-F9AE-4B07-969E-05C26BC060D8}", $appsecPart)
    
    function Add-AppSec {
    
        param (
            $path
        )
        $v = (Get-ItemProperty -Path $path).Environment
        If ($v -eq $null) {
            Set-ItemProperty -Path $path -Name "Environment" -Value $defaultvariable
        }
        ElseIf (-not ($v -match $appsecPart)) {
            $v += " " + $appsecPart;
            Set-ItemProperty -Path $path -Name "Environment" -Value $v
        }
    }
    Add-AppSec -path "HKLM:SYSTEM\CurrentControlSet\Services\WAS\"
    Add-AppSec -path "HKLM:SYSTEM\CurrentControlSet\Services\W3SVC\"
    
    net stop was /y
    net start w3svc
    

    Or, to avoid editing registry keys, edit the application settings in the web.config file of your application:

    <configuration>
      <appSettings>
            <add key="DD_APPSEC_ENABLED" value="true"/>
      </appSettings>
    </configuration>
    

    This can also be done at the IIS application pools level in the applicationHost.config file, usually in C:\Windows\System32\inetsrv\config\:

    <system.applicationHost>
    
        <applicationPools>
            <add name="DefaultAppPool">
                <environmentVariables>
                    <add name="DD_APPSEC_ENABLED" value="true" />
                </environmentVariables>
                (...)
    

    Add the following to your application configuration:

    DD_APPSEC_ENABLED=true
    

    Update your configuration container for APM by adding the following argument in your docker run command:

    docker run [...] -e DD_APPSEC_ENABLED=true [...] 
    

    Add the following environment variable value to your container Dockerfile:

    ENV DD_APPSEC_ENABLED=true
    

    Update your deployment configuration file for APM and add the ASM environment variable:

    spec:
      template:
        spec:
          containers:
            - name: <CONTAINER_NAME>
              image: <CONTAINER_IMAGE>/<TAG>
              env:
                - name: DD_APPSEC_ENABLED
                  value: "true"
    

    Update your ECS task definition JSON file, by adding this in the environment section:

    "environment": [
      ...,
      {
        "name": "DD_APPSEC_ENABLED",
        "value": "true"
      }
    ]
    

    Add the following line to your container Dockerfile:

    ENV DD_APPSEC_ENABLED=true
    
  3. Restart the application using a full stop and start.

    After this configuration is complete, the library collects security data from your application and sends it to the Agent, which sends it to Datadog, where out-of-the-box detection rules flag attacker techniques and potential misconfigurations so you can take steps to remediate.

  4. To see Application Security Management threat detection in action, send known attack patterns to your application. For example, trigger the Security Scanner Detected rule by running a file that contains the following curl script:

    for ((i=1;i<=200;i++)); 
    do
    # Target existing service’s routes
    curl https://your-application-url/existing-route -A dd-test-scanner-log;
    # Target non existing service’s routes
    curl https://your-application-url/non-existing-route -A dd-test-scanner-log;
    done

    Note: The dd-test-scanner-log value is supported in the most recent releases.

    A few minutes after you enable your application and exercise it, threat information appears in the Application Signals Explorer and vulnerability information appears in the Vulnerability Explorer.

Further Reading