Wikipedia says this about religion in Kazakhstan:

Islam is the largest religion in Kazakhstan, followed by Russian Orthodox Christianity. Kazaks are mainly Sunni Muslims of the Hanafi school, and the Russians are Russian Orthodox. In 1994, some 47 percent of the population was Muslim, 44 percent was Russian Orthodox, and 2 percent was Protestant, mainly Baptist.[26] Based on a 2007 data of, The Embassy of the Republic of Kazakhstan in the UK, Islam was practiced by 57% of the population, Christianity 40% and other religions 3%.

Radical religious organizations, despite a popular belief, are of little danger to the national security. The few organizations that were uncovered are being investigated thoroughly by the proper committee. Therefore, Kazakhstan has a very diverse, stable, and safe religious background – a truly exceptional occurrence.

The Senate in Kazakhstan, after approval in the house, is reviewing a dramatic and draconian reform of laws governing “approved” religions in the country.

[Forum 18]The text of the Law as approved by the lower house – and seen by Forum 18 – would for the first time explicitly ban unregistered religious activity, ban sharing beliefs by individuals not named by registered religious organisations and without personal registration as missionaries, require all registration applications to be approved centrally after a “religious expert assessment” of each community’s doctrines and history, and impose a wider range of fines on individuals and communities and bans on religious communities who, for example, conduct activity not specifically mentioned in their charter. Groups without full registration would not be able to maintain publicly-accessible places of worship.

So which religion is going to get the short end of the stick when it comes to official approval? Not the Orthodox as they constitute a very large percentage of the population. It is interesting to note that in 1991, a Catholic diocese was founded in the country and that some protestant denominations have made some headway in the country as well. Whichever religion is on the non-approved list, this is not a good time for religious liberty in Kazakhstan.