Control: 1.13 Ensure API keys are restricted to use by only specified Hosts and Apps

Description

Unrestricted keys are insecure because they can be viewed publicly, such as from within a browser, or they can be accessed on a device where the key resides. It is recommended to restrict API key usage to trusted hosts, HTTP referrers and apps.

Security risks involved in using API-Keys appear below:

• API keys are simple encrypted strings
• API keys do not identify the user or the application making the API request
• API keys are typically accessible to clients, making it easy to discover and steal an API key

In light of these potential risks, Google recommends using the standard authentication flow instead of API keys. However, there are limited cases where API keys are more appropriate. For example, if there is a mobile application that needs to use the Google Cloud Translation API, but doesn't otherwise need a backend server, API keys are the simplest way to authenticate to that API.

Remediation

From Console

To find the listed API Keys with specified Hosts access and Apps

1. Login to APIs & Services\Credentials
2. In the section API Keys, Click the API Key Name. The API Key properties display on a new page.
3. For every API Key, ensure below

• Application restrictions is not set to None.
• API restrictions is not set to Don't restrict key

Alternatively you can set values as example:

• Ensure Application restrictions is set to HTTP referrers and the referrer is not set to wild-cards (* or *.[TLD] or *.[TLD]/*) allowing access to any/wide HTTP referrer(s)

Or,

• Ensure Application restrictions is set to IP addresses and referrer is not set to any host (0.0.0.0 or 0.0.0.0/0 or ::0)

Note By default, Application Restrictions are set to None.