Your AdSense ID is public through view source. I do not know how secure it is, but trust Google to know what they do. Comission Junction has the option to encrypt the link code.
There is now a new form of hijacking:
1. You are invited to join a forum with profit sharing via Google AdSense.
2. You use your code on their site and Google Adsense Ad are shown on the sites you post on.
3. You are told that you earn money on your Ad's, but most probably there is a redirection to the owners account. When people click on "your AdSense" there is in other words a mapping of your ID to the owners ID.
4. You are also invited to participate in other Ad programs, like PPC programs, most probably to get your Paypal information and credit card information.
Related post:
Hijacking has as many faces as there are people. It is estimated (do not remember the source) that about 30 % of your hard earned affilate commision is stolen by hijackers. It comes in different forms. The most obvious is to replace your tracking code with the hijackers code.
http://www.webproworld.com/viewtopic...06c21c30eba8d6