Instalation media for security repository mirror

Problem:
I would like to use mine mirror of security.ubuntu.com during instalation. When I set installation media http://mirror.example.com/ubuntu/ it is populated to /etc/apt/sources.list but without seccurity - it is set to to global security.ubuntu.com, which leads to mismatch in packet versions from my (older) mirror and can’t use my mirror of security repo from ubuntu. Where can I change this behavior ? in which provisioning template ?

Foreman 1.22

Strange to answer for my self, but :slight_smile: … I did managed to do it by editing preseed for ubuntu:

# security mirror
d-i apt-setup/security_host string <%= host_param('security_mirror_server') %>
d-i apt-setup/security_path string <%= host_param('security_mirror_path') %>