Troubleshooting

DNS Sever will not start

1. On Linux unsure that dnsmasq is not running. If it is kill it.
2. On Linux and using port 53 make sure you ran burp as root. Otherwise you can run on 5353 and use iptables to redirect UDP on 53 to the high port number.
3. On Windows disable the firewall.

Invisible proxies are not starting on 80 and 443

1. On Linux you will need to run burp as root.
2. On Windows disable the firewall.

SSL listeners are not working.

1. Ensure you have exported Burp's CA certificate correctly. Follow these steps
2. Ensure that the 'Certificate HostName' input matches the real hostname before creating the SSL listener in NoPE.
3. Ensure the ports are correct. Not all applications use port 443 to send encrypted data to the server.

Python Manger does not run my code while requests go unmodified.

The mangler is set send the original request if there is an error in the python code. This prevents dropping the session until the code is entered correctly. Try to run your code in a normal python interpreter to ensure there are no errors before running it in NoPE.

A trick to test your code is to take the request you want to modify; Select it in Burp; Then right click and 'Copy to File'. Then you can run your code outside of NoPE with the following modifications.

def mangle(input,isC2S):
   return input

f=open('binary.out','r')
data=f.read()
print mangle(data,True)

Also if you modify the input variable in your code as a string you may need to convert back to a byte array before NoPE can understand it. You can use the bytearray() function as shown below.

def mangle(input,isC2S):
   input=input.replace("test data","replaced data")
   return bytearray(input)

NoPE won't start and extension never loads in Burp.

The most likely reason is the Traffic Database has been corrupted. To fix this issue just delete it and restart NoPE. The database is located in ~/.NoPEProxy/requests.sqlite