1 "Linux User Namespaces Might Not Be Secure Enough" by Erica Windisch: If a (real) root user has had the SYS_CAP_ADMIN capability removed, but then creates a user namespace, this capability is restored for the (fake) root user. That is, before creating the namespace, ‘mount’ would be denied, but following the creation of the user namespace, the ‘mount’ syscall would magically work again, albeit in a limited fashion. While limited in function, it’s significant enough that given a (real) root use...