Information
Azure App Service allows apps to run under both HTTP and HTTPS by default. Apps can be accessed by anyone using non-secure HTTP links by default. Non-secure HTTP requests can be restricted and all HTTP requests redirected to the secure HTTPS port. It is recommended to enforce HTTPS-only traffic.
Rationale:
Enabling HTTPS-only traffic will redirect all non-secure HTTP requests to HTTPS ports. HTTPS uses the TLS/SSL protocol to provide a secure connection which is both encrypted and authenticated. It is therefore important to support HTTPS for the security benefits.
Impact:
When it is enabled, every incoming HTTP request is redirected to the HTTPS port. This means an extra level of security will be added to the HTTP requests made to the app.
Solution
Remediate from Azure Portal
Login to Azure Portal using https://portal.azure.com
Go to App Services
For each App Service
Under Setting section, click on Configuration
Under the General Settings tab, set HTTPS Only to On under Platform Settings
Remediate from Azure CLI
To set HTTPS-only traffic value for an existing app, run the following command:
az webapp update --resource-group <RESOURCE_GROUP_NAME> --name <APP_NAME> --set httpsOnly=true
Remediate from PowerShell
Set-AzWebApp -ResourceGroupName <RESOURCE_GROUP_NAME> -Name <APP_NAME> -HttpsOnly $true
Default Value:
By default, HTTPS-only feature will be disabled when a new app is created using the command-line tool or Azure Portal console.