Depends on their popularity and how much they demand.
But look at this link from season 4 and factor in the inflation:
http://www.techtipspro.com/2010/10/bigg-boss-4-celebrity-payment-rates.html
Last season I think I heard Karisha counting 1 lakh per week if I heard correctly.
For this season, apparently Poonam Pandey was demanding 3 crore for the entire season.
Shoaib akhtar wanted 1 crore for the entire season.
Every one else in the house is much, much lower in star status compared to Shoaib Akhtar so I'm assuming these people aren't getting paid much at all. They are really just doing it for their career and to stay relevant.