AWS Research and Engineering Studio (RES) is an open-source solution that enables researchers and engineers to create and manage secure virtual desktops and computing resources on AWS. Improper link resolution before file access issue (CWE-59) in the Auth.GetUserPrivateKey API. An authenticated remote user could read arbitrary files on the cluster-manager EC2 instance by replacing their SSH private key file (~/.ssh/id_rsa) with a symbolic link targeting any file on the host. Because the cluster-manager process runs as root, any file readable by root is exposed, including other users' SSH private keys and application configuration secrets. It's recommended to upgrade to RES version 2026.06.