FastGPT is an AI Agent building platform. In versions 4.14.8.3 and below, the fastgpt-preview-image.yml workflow is vulnerable to arbitrary code execution and secret exfiltration by any external contributor. It uses pull_request_target (which runs with access to repository secrets) but checks out code from the pull request author's fork, then builds and pushes Docker images using attacker-controlled Dockerfiles. This also enables a supply chain attack via the production container registry. A patch was not available at the time of publication.