De acordo com a documentação do kali-linux, você deve usar o repositório kali-rolling em seu sources.list
:
Como deve ser minha sources.list?
Kali rolling users should have these entries in their /etc/apt/sources.list file:
deb http://http.kali.org/kali kali-rolling main non-free contrib
For a more in-depth description of possible entries in your sources.list, check this post.
The Kali Rolling Repository
kali-rolling is our current active repository since the release of Kali 2016.1. Kali Rolling users are expected to have the following entries in their sources.list:
deb http://http.kali.org/kali kali-rolling main contrib non-free
O kali sana é aposentado.
Transição de Kali 2.0 para Kali Rolling
Migrating from Kali sana (2.0) to Kali rolling is simple. As root, you can run the following commands and be on your way:
cat << EOF > /etc/apt/sources.list
deb http://http.kali.org/kali kali-rolling main non-free contrib
EOF
apt-get update
apt-get dist-upgrade
reboot
Observe que os repositórios do Kali Sana não serão mais atualizados e serão exibidos no dia 15 de abril de 2016.