Crikey, was CrikeyCon FUN!
I am still overwhelmed by the amazing and super positive response from my presentation at this year’s inaugural CrikeyCon. I really didn’t expect anywhere near the reaction from those who attended, it has taken the last few days for everything to really sink in. I never expected people to be so amazed by the lateral movement capabilities of PowerShell combined with WinRM, I expected some to be shocked but not as many as I did.
As requested, you can find the slide deck here, and the GitHub code is available here. If you take a look through my GitHub repositories, you will notice how much PowerShell code I normally write, and you can also see the previous version of the same code.
I have to admit, there are two minor inaccuracies in my presentation. One makes things better, the other makes things much, much worse.
1. In the slides I stated that “WinRM is enabled by DEFAULT on domain 2012(R1/R2) joined servers”. I gathered this from Microsoft, but upon further investigation, this link from Microsoft actually states the situation is much worse: “In Windows Server 2012 R2 and Windows Server 2012, remote management is enabled by default.”
2. During question time, I said that installing the Windows Remote Management 4.0 bundle onto Windows 2008 (R1/2) servers, will enable WinRM for domain joined systems. I currently don’t believe this to be true, there doesn’t seem to be any confirmation from Microsoft, I am still testing in my lab and will let you all know.
I am currently working on an extended video of my presentation, in which I will go into more detail around each of the issues and will show the code in detail as well. I am also planning on writing a paper which will discuss using PowerShell and WinRM for lateral movement, possible attack vectors as well as strategies to protect your environment. Once these have been completed, I will let you all know.
I would really like to thank Ash and Wade for convincing me to speak and for organising CrikeyCon as well as Patrick over at Risky.biz for being an excellent MC.
Lastly, sorry for the lame title for this post.
Once again:
Running 32Bit PowerShell Jobs
Occasionally, you might need to run something in PowerShell that needs to strictly be run under a 32bit session. This can be very annoying, here is a trick, use the PowerShell jobs to your advantage!
Start-Job -Name 32bitjobs -RunAs32 -ScriptBlock { <CODE HERE> }
Receive-Job -Name 32bitjobs
This will start the script blog as a 32bit PowerShell session. Start-Job actually kicks off a separate PowerShell.exe instance, so make sure everything that script block needs is available.
PowerShell Error: The specified structure must be blittable or have layout information.
So recently I was working with the Get-TSLsaSecret CMDLet which was written by Niklas Goude, a guest blogger from TrueSec who was writing on the Hey Scripting Guy Blog.
You can find the write up on the CMDLet here, It is also worth reading the previous post in the series here.
Everytime I ran the CMDLet, ensuring that I was running as a 32bit session, which was elevated, I would receive the message "The specified structure must be blittable or have layout information.", I looked and looked and couldn't see anything I was doing wrong, or anything wrong in the code.
I the stumbled upon Microsoft KB 2909958. Resolving the issue is very simple, we just need to do another cast on the line with the error.
In the code from Microsoft/Niklas, change:
[LSAUtil.LSAUtil+LSA_UNICODE_STRING] [System.Runtime.InteropServices.marshal]::PtrToStructure($privateData, [LSAUtil.LSAUtil+LSA_UNICODE_STRING])
to:
[LSAUtil.LSAUtil+LSA_UNICODE_STRING][System.Runtime.InteropServices.marshal]::PtrToStructure($privateData, [System.Type][LSAUtil.LSAUtil+LSA_UNICODE_STRING])
And you are done!
More to come on Get-TSLsaSecret!!!!
Tools of the trade
I have been asked a few times what gear I use, for work and for personal use.
Hardware
I use three computers on a regular basis, a personal laptop/tablet, work laptop and then my gaming rig.
Firstly there is my simply fantasic Surface Pro 2 (128GB SSD, 4GB of RAM), this is one of the most amazing devices I have used, I am simply surprised by how much I can do with it.
I have my tweaked out HP EliteBook Folio 9470m, this is my work device. It isn't spec-ed out how you would get it normally from the shop, or even HP internally. Featuring a similar CPU as the Surface Pro 2, but with 256GB SSD and 16GB of RAM. Compared to all other work devices I have had over the years, it is by far the best. It is quite light, and packs a very nice 15 inch screen. The only limitation is there is no ESATA, but it has an abundance of USB3 ports.
Finally I have my gaming rig, not much to say but I7, 24GB of RAM, tonnes of storage and a beast video card to boot all on a Gigabyte Sniper 2 motherboard. I game and code on this thing on a regular basis.
Software
Must Haves
- Windows 8.1 X66
- Office 2013
Development/PowerShell
- PowerShell (obviously)
- Visual Studio 2013
- PrimalScript 2012
- Notepad++
- Winmerge
- GitHub for Windows
- Tortise SVN
Networking/Security
- Bitvise SSH Client
- Virtualbox
- Tor
- CCLeaner
- GPG
- Putty
- F Secure AV
- Inssider
- NMap
- WireShark
- EMET
- OpenVPN
- Keepass
- SMAC
Media
- VLC
- Winamp
Communications and Social Media
- Hexchat
- Line
- Skype
- Lync
And the Rest...
- Wunderlist
- Firefox
- Feedly
- Kindle
- 7Zip
- Cashplan
- Foxit Reader
- Steam
Peripherals
Nothing really special here. I like a good keyboard and mouse, preferably gaming gear like G510 etc.
My Partner bought me some fantastic Sony headphones for Christmas, the Sony MDR-1RBT Mark2. Quite amazing, Bluetooth, NFC and 30 hour battery life!
So that is pretty much it. I will try and keep this updated as I change what I am using.
What am I reading?
Just a quick post about the blogs found in my RSS reader. It is all pretty self explanatory!
Comics
PHD Comics http://www.phdcomics.com
Penny Arcade http://www.penny-arcade.com
xkcd.com http://xkcd.com/
Dilbert http://dilbert.com/
Microsoft (and related) blogs
Security Research & Defense http://blogs.technet.com/b/srd/
Powershell.CA http://www.energizedtech.com/
MSRC http://blogs.technet.com/b/msrc/
Richard Hicks' DirectAccess Blog http://directaccess.richardhicks.com
Microsoft Security Bulletins http://technet.microsoft.com/security/bulletin
Jeff Alexander's Weblog http://blogs.technet.com/b/jeffa36/
istartedsomething http://www.istartedsomething.com
Ben Armstrong http://blogs.msdn.com/b/virtual_pc_guy/
Bink.nu News http://www.bink.nu
WinBeta | Microsoft centered, Technology focused http://www.winbeta.org
Group Policy Central http://grouppolicy.biz
Security
Darknet - The Darkside http://www.darknet.org.uk
F-Secure Antivirus Research Weblog http://www.f-secure.com/weblog
security.crudtastic.com http://security.crudtastic.com
Hak5 - Technolust since 2005 http://hak5.org
Schneier on Security https://www.schneier.com/blog/
Packet Storm Security http://packetstormsecurity.com/
General
IFTTT Blog http://blog.ifttt.com/
Ars Technica http://arstechnica.com
LifeHacker Australia http://lifehacker.com.au
The Food Avenue...Diary of a food addict http://thefoodavenue.com
DirectAccess Resources
So I have been spending quite a significant amount of time working on DirectAccess and generally talking to people about DirectAccess, remote access and working remotely in generally over the past few months.
DirectAccess was a technology that I had wanted to work with for a significantly long period of time, the concept of an always on VPN like it has always interested me. I was extremely excited to be given the opportunity to work with it!
Not only did I get the opportunity to deploy DirectAccess in an enterprise environment, but I also had the chance to share my experience with the Brisbane Infrastructure Group. My presentation can be found here.
So I thought why not provide you all with links to some of the resources that I used during my deployment of DirectAccess
Blogs:
Richard Hicks (MVP DirectAccess) - http://directaccess.richardhicks.com/
Tom Shinder (MVP DirectAccess / TMG) - http://blogs.technet.com/b/tomshinder
Iron Networks - http://www.ironnetworks.com/blog/
Specific articles you should read:
http://www.ivonetworks.com/news/2013/10/is-isatap-required-for-directaccess/
http://www.ironnetworks.com/blog/application-compatibility-issues-microsoft-directaccess
http://www.ironnetworks.com/blog/directaccess-network-location-server-considerations
http://www.ironnetworks.com/blog/common-directaccess-implementation-mistakes
There are probably some links missing, if there are other things that I realize I have missed, I will update this post.
DirectAccess with Computer Certificates and SHA512 algorithms
I have posted this as a question on the TechNet forums, but also wanted to post it here.
I have just finished another test lab deployment of Direct Access, and have noticed one interesting issue which I am trying to confirm.
In the lab I deployed the PKI part of the infrastructure quite a while ago, its a typical deployment, with an offline root and online issuing authority. They were configured to use the SHA512 for the Signature and Signature Hash algorithms. This selection might seem paranoid, but has never been an issue as all clients have been Windows 7 or higher and thus have full support.
I deployed direct access, and using basically the default settings, everything appears to be working correctly, clients could successfully connect.
I then switched to requiring computer certificates, issued a certificate to the DA Server and the test clients based upon the "Computer" template.
Clients could no longer connect. Looking at the diagnostic logs for Direct Access it appeared that the tunnels were not being established correctly. Looking at get-DAConnectivityStatus, there was definitely an issue present, with a sub status error referring to errors with remote network authentication. Nothing really appeared out of the ordinary in the client diagnostic logs or event viewer.
I went looking on the server, nothing appeared at first to point to a problem, however on inspection of the system event log, there were errors in regards to TLS:
'An TLS 1.2 connection request was recieved from a remote client application, but none of the cipher suites supported by the client application are supported by the server. The SSL connection request has failed'
So I looked around and didn't find anything out there, I couldn't see anything obvious, then it occurred to me that we are using SHA512 in our certificates.
I quickly fired up a new CA in the test environment, this time basically accepting the defaults. Reissued certificates computer certificates to the DA server and the test clients, and I am now successfully connecting.
Does anyone know of this incompatibility? is it documented anywhere? IS this known by anyone? Has anyone seen this as well?
Any more info would be great.
Password Hashing with BCrypt and PowerShell - Part 3
Final remarks on the password hashing.
The code is all up on GitHub, https://github.com/kjacobsen/PSBCrypt
I don't know if any of this has been useful to anyone, but maybe I have explained a little about secure password hashing and helped prevent some poor implementations.
Thank you all for reading this series.