The Visualizer WordPress plugin before 4.0.6 does not restrict a user-supplied URL to safe address ranges before fetching it server-side, allowing users with Contributor-level access and above to pe…

Summary

The Visualizer WordPress plugin before 4.0.6 does not restrict a user-supplied URL to safe address ranges before fetching it server-side, allowing users with Contributor-level access and above to perform Server-Side Request Forgery against link-local instance-metadata endpoints. As the fetched response is returned in the reply, the attack is non-blind, enabling retrieval of cloud instance metadata (including IAM credentials) on cloud-hosted sites.