536923 Make Penetration Test for a website

Hi all! I have just 5 day to make a penetration test for a website (PM me). This website i'm testing has already some know vulnerabilities like "SSL Renegotiation" and i discovered squid url patch on it.. but i can't able to scan it because maybe they have software like mod_security that block clients that send more dangerous request to test... Well i can't do it all alone. i need help from others experts. You will be paid only after discovered the bug bud before tell me all you need to introduce what type of bug is or what are the causes. this site are under one ip load balancer that have some squid+openbsd proxy. Backend are microsoft windows. Thankyou ;)