I ran nessus and it found the following vulnerability:
Synopsis: The proxy allows the users to perform CONNECT requests like CONNECT http://cvs.nessus.org:23/
This request give to the person who make it the ability
to have an interactive session.
This problem may allow attackers to go through your
firewall, by connecting to sensitive ports like 23 (telnet)
using your proxy, or it can allow internal users to bypass the firewall
rules and connect to ports they should not be allowed to.
Solution reconfigure your proxy so that it refuses CONNECT requests.
Risk Factor : High
How can I make the configuration shange suggestted in the solution or all together turn off this proxy?