Advanced security settings

Enterprise plan only This feature is only available in custom enterprise pricing plans.

ImageKit provides advanced security and optimization features that you can use to optimize your asset delivery flow and save costs.

It includes the following features:

1. IP and IP range blocking.

2. Optimized asset delivery based on user agents.

3. Geographic restriction.

4. HTTP Referrer-based restriction.

5. User Agent based restriction.

6. Improved caching of assets.

Advanced security settings in ImageKit's dashboard

How to configure?

If your plan includes this feature, please contact us at [e-mail] to set it up for your account. Once it is enabled and configured, you can use this feature from your ImageKit account's dashboard.

IP and IP range blocking

Limits

• You can block at most 100 absolute IPs or IP ranges.

• Only IPv4 blocking is supported.

This feature blocks absolute IPs or IP ranges from accessing content. Any request from these unauthorized IPs would result in an HTTP 403 error response, and the asset will not be delivered.

To block IPs, you need to provide a list of valid absolute IPv4 addresses or IPv4 ranges in CIDR notation separated by a new line in the input - using the advanced security settings in the dashboard.

Examples of valid input-

• Absolute IPv4 - 163.120.4.15.

• IPv4 range using CIDR notation - 10.0.0.0/24. This blocks all IPs in range 10.0.0.0 to 10.0.0.255.

Optimized asset delivery based on user agents

Limits

• You can configure at most 10 user agents for WebP image delivery.

You can set the user agents for which you want to deliver optimized assets using this feature. Using this, you can serve optimized images on your application.

To configure this setting for your requests, go to the advanced security settings on the dashboard to provide a list of user agents, each separated by a new line.

These user agents do not have to be an exact match to the user agent header sent in the request. If the user agent in your request has any of the defined user agents as a substring, ImageKit will send the optimized asset. User agent match is case-insensitive.

For requests that have one of the configured user agents, you can select the accept header from the options given in the drop-down menu. This helps in the detection of the format of the asset to be delivered as well as in caching.

For example:

• If you configure the user agent Android 11 and accept headers for the configured user agents image/webp,image/apng,*/*;q=0.8, for a request having the user agent header Linux; U; Android 11, ImageKit would deliver a WebP image.

Geographic restriction

ImageKit provides geographic restriction that allows you to restrict access to assets at the country level.

There are three options for geographic restriction-

• Blocklist

• Allowlist

• No restriction

By default, no geographic restrictions are applied.

HTTP Referrer-based restriction

Limits You can allow or block at most 30 referrers.

The Referer HTTP request header contains an absolute or partial address of the page that makes the request. The Referer header allows a server to identify a page where people are visiting it from.

Referrer-based restriction ensures that content only loads on requests from authorized domains. Any unauthorized request will result in an HTTP 403 error, and the asset will not be delivered.

ImageKit provides three options for referrer restriction-

• Blocklist

• Allowlist

• No restriction

For blocking or allowing domains, you need to provide a list of valid URLs (Each URL must include at least the scheme and domain name) separated by a new line. The exact domain mentioned in the URLs would be allowed or blocked.

For example:

• If you add https://ik.imagekit.io to the allowlist, the URL ik.imagekit.io will be allowed.

• If you add https://developer.mozilla.org/en-US/search?q=URL to the blocklist, the domain developer.mozilla.org will be restricted.

Note: Wildcard domain restrictions are not supported as of now.

Uses

Using the blocklist will block domains that are hotlinking your content or assets, increasing your bandwidth usage and hosting costs. The blocklist saves costs significantly if your assets are undesirably hotlinked on other websites.

The allowlist can be used to allow only selected domains to access your assets. For example, you can use it to serve content only on your allowed domains and automatically block other referrers.

If you do not want any HTTP referrer restriction, you can opt for no restriction, which is the default behavior.

User Agent based restriction

Limits

• You can configure at most 10 user agents to block.

This feature blocks user agents from accessing content. Any request with a blocked user agent will result in an HTTP 403 error, and the asset will not be delivered.

To configure this setting for your requests, go to the advanced security settings on the dashboard to provide a list of user agents, each separated by a new line.

These user agents do not have to be an exact match to the user agent header sent in the request. If the user agent in your request has any of the defined user agents as a substring, ImageKit will block the request. User agent match is case-insensitive.

For example:

• If you configure the user agent Bytespider, for a request having the user agent header Linux; U; Bytespider/3.0, ImageKit would block the request.