CVE-2025-25297: Label Studio Server-Side Request Forgery via S3 Endpoint

Label Studio lets users connect S3 storage and supply a custom endpoint through the s3_endpoint parameter. The value goes straight to the boto3 SDK with no restriction on protocol or destination.

An attacker points the endpoint at an internal service and triggers a storage sync. Label Studio makes S3 API calls to that address, and the error message returns the full response body. That turns a storage setting into a way to read from services behind the firewall. Label Studio 1.16.0 fixes the issue.