Note that Turris currently only supports privileged containers. Here is what the LXC developers say about the security of privileged containers:
“[…] they’re not safe at all and should only be used in environments where unprivileged containers aren’t available and where you would trust your container’s user with root access to the host.”
“As privileged containers are considered unsafe, we typically will not consider new container escape exploits to be security issues worthy of a CVE and quick fix.”
“We are aware of a number of exploits which will let you escape such containers and get full root privileges on the host.”
Source: https://linuxcontainers.org/lxc/security/
EDIT: I really hope that the Turris team will consider implementing unprivileged containers. Forum user @nerdpunk already did the work: Multiple virtual servers (LXC containers) possible?