HOWTO : Flash Plugin on Kali Linux 1.0.9a

Iceweasel

To install Flash :
apt-get install flashplugin-nonfree

To update Flash :
update-flashplugin-nonfree --install

Google Chrome

nano /etc/apt/sources.list

Append the following line :

deb http://http.debian.net/debian wheezy-backports main contrib non-free

To install Flash :

apt-get update
apt-get -t wheezy-backports install pepperflashplugin-nonfree

Make sure to comment out the newly added repos after the install :

#deb http://http.debian.net/debian wheezy-backports main contrib non-free

To update Flash :
update-pepperflashplugin-nonfree --install

That's all! See you.