| name | cis-azure-compute-2.3.6 |
| description | Ensure 'HTTPS Only' is set to 'On' |
| category | cis-azure-compute |
| version | 2.0.0 |
| author | cyberstrike-official |
| tags | ["cis","azure","function-apps","https","tls","encryption","data-in-transit"] |
| cis_id | 2.3.6 |
| cis_benchmark | CIS Microsoft Azure Compute Services Benchmark v2.0.0 |
| tech_stack | ["azure"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
Ensure 'HTTPS Only' is set to 'On'
Description
Azure App Service allows function apps to run under both HTTP and HTTPS by default. Function 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 deployment slot.
Audit Procedure
Using Azure Portal
- Go to
App Services or Function App.
- Click the name of a function app.
- Under
Settings, click Configuration.
- In the
General settings tab, under Platform settings, ensure that HTTPS Only is set to On.
- Repeat steps 1-4 for each function app.
Using Azure CLI
Run the following command to list function apps:
az functionapp list
For each function app, run the following command to get the HTTPS setting:
az functionapp show --resource-group <resource-group-name> --name <function-app-name> --query "httpsOnly"
Ensure that the command returns true.
Using Azure PowerShell
Run the following command to list function apps:
Get-AzFunctionApp
Run the following command to get the function app with a given name:
$app = Get-AzFunctionApp -ResourceGroupName <resource-group-name> -Name <function-app-name>
Run the following command to get the HTTPS setting for the function app:
$app.httpsOnly
Ensure that the command returns True. Repeat for each function app.
Expected Result
The httpsOnly setting should return true.