Description:
Periodically newer versions are released for PHP software either due to security flaws or to include additional functionality. Using the latest PHP version for web apps is recommended in order to take advantage of security fixes, if any, and/or additional functionalities of the newer version.
Rationale:
Newer versions may contain security enhancements and additional functionality. Using the latest software version is recommended in order to take advantage of enhancements and new capabilities. With each software installation, organizations need to determine if a given update meets their requirements. They must also verify the compatibility and support provided for any additional software against the update revision that is selected.
Impact:
If your app is written using version-dependent features or libraries, they may not be available on the latest version. If you wish to upgrade, research the impact thoroughly. Upgrading may have unforeseen consequences that could result in downtime
.
Audit:
From Azure Portal
1. From Azure Home open the Portal Menu in the top left
2. Go to App Services
3. Click on each App
4. Under Settings section, click on Configuration
5. Click on the General settings pane, ensure that for a Stack of PHP the Major Version and Minor Version reflect the latest stable and supported release. ** The latest stable version can be confirmed by going to php.net. Navigate to the downloads, and then find the most recent version that is marked by Current Stable PHP [version_number]. **
NOTE: No action is required If PHP version is set to Off as PHP is not used by your web app.
From Azure CLI
To check PHP version for an existing app, run the following command,
az webapp config show --resource-group <RESOURCE_GROUP_NAME> --name
<APP_NAME> --query "{LinuxFxVersion:linuxFxVersion,PHP_Version:phpVersion}"From PowerShell
$application = Get-AzWebApp -ResourceGroupName <resource group name> -Name
<app name>
$application.SiteConfig | select-object LinuxFXVersion, phpVersionThe output should return the latest available version of PHP. Any other version of PHP would be considered a finding.
NOTE: No action is required, If the output is empty as PHP is not used by your web app.
Remediation:
From Azure Portal
1. From Azure Home open the Portal Menu in the top left
2. Go to App Services
3. Click on each App
4. Under Settings section, click on Configuration
5. Click on the General settings pane, ensure that for a Stack of PHP the Major Version and Minor Version reflect the latest stable and supported release
.
NOTE: No action is required If PHP version is set to Off or is set with an empty value as PHP is not used by your web app.
From Azure CLI
List the available PHP runtimes:
az webapp list-runtimesTo set latest PHP version for an existing app, run the following command:
az webapp config set --resource-group <resource group name> --name <app name>
[--linux-fx-version <php runtime version>][--php-version <php version>]From PowerShell
To set latest PHP version for an existing app, run the following command:
Set-AzWebApp -ResourceGroupName <resource group name> -Name <app name> -
phpVersion <php version>NOTE: Currently there is no way to update an existing web app Linux FX Version setting using PowerShell, nor is there a way to create a new web app using PowerShell that configures the PHP runtime in the Linux FX Version setting.
Default Value:
The version of PHP is whatever was selected upon App creation.
References:
1. https://docs.microsoft.com/en-us/azure/app-service/web-sites-configure#generalsettings