Abstract: An instance secrets management isolated runtime environment is launched at a virtualization server, and utilizes a subset of memory assigned to a compute instance. The subset of memory is inaccessible from entities external to the runtime environment. A secrets manager of the runtime environment provides a security artifact to an application, running at the compute instance, which has requested access to a resource. The artifact is generated by the secrets manager using a security secret associated with the compute instance; the secret is not accessible to programs external to the runtime environment. In response to a determination that the artifact is valid, the application obtains access to the resource.