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NTLM 100% Broken Using Hashes Derived From Captures
New submitter uCallHimDrJ0NES writes "Security researcher Mark Gamache has used Moxie Marlinspike's Cloudcracker to derive hashes from captured NTLM handshakes, resulting in successful pass-the-hash attacks. It's been going on for a long time, probably, but this is the first time a 'white hat' has researched and exposed the how-to details for us all to enjoy. 'You might think that with all the papers and presentations, no one would be using NTLM...or, God forbid, LM. NTLMv2 has been around for quite some time. Surely, everyone is using it. Right? Wrong! According to the last data from the W3 Schools, 21% of computers are running XP, while NetMarketShare claims it is 39%. Unless someone has hardened these machines (no MS patches do this), these machines are sending LM and NTLM responses!' Microsoft has posted a little guidance for those who need to turn off NTLM. Have fun explaining your new security project to your management, server admins!"
NTLM stands for Windows NT Lan Manager. Is was used in earlier Windows from NT 3.1 (yes THAT old) up til Win 2K3 IIRC.
Users would authenticate their login credentials to the system. NTLM is the sub-system that does that authentication.
For more details see wikipedia: http://en.wikipedia.org/wiki/NTLM
The Microsoft article http://support.microsoft.com/kb/2793313 referenced above points to http://technet.microsoft.com/library/cc960646.aspx
You can also use Group Policy:
http://technet.microsoft.com/en-us/library/cc738867(v=ws.10).aspx
How to harden those XP machines and make them use NTLM2 instead?
My blanket recommendation for hardening XP machines is to encase them in concrete.
I'd say this affects Linux too - a bunch of machines with Samba are quite possibly vulnerable, and need a different settings change than what Windows does.
At a minimum, the following in the smb.conf
[global]
client ntlmv2 auth = yes
lanman auth = no
ntlm auth = no
For winbindd, a recompile might be required.
It is time to get with the times.
Yes, I worked in corporate I.T. before and know all the tired arguments. The OS will turn 13 years old later this year. 13 years?!
Not to mention XP SP 3 after 800 or so updates is slower and not the speed daemon it once was as 9 out of 10 CPU cycles are work around exploits. Stop defining yourselves and your ego on an OS made by the same people who wrote IE 6?
The idea for security in XP is from the last century where all you needed is a good password. It lacks things a modern internet enabled OS have today. It is not a trendmill at this point nor is MS being evil to the mean old beancounters who refuse to see hidden costs and just licensing on a spreadsheet in excel. This story, the one on IE 6-8 being vulnerably last week on slashdot, and many others stating XP is so primptive because it doesn't have protected mode, ASLR, are DEP fully (only a few things have that on XP).
If you ask this because your IT department has no plans to upgrade then another job who treat your profession and seriousness with respect.. They are incompetent and when shit hits the fan and social security numbers are stolen you will get the blame as the cost center and be let go anyway.
It is obvious with the latest security issues in IE6, IE 7-8 (in non protected mode), XP, and now this that it is time to let it go instead of workaround it. Investing time and money into it is like investing cash into a car with 200,000 miles.
These costs are real and so are the liabilities. Grow a pair and sell yourself the cheap asshats at your company? You are not saving anything by keeping an outdated insecure infrastructure and it is not unreasonable to upgrade to a 3 year old OS.
http://saveie6.com/