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George R. KasicaFlag for United States of America

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Setting Windows Ciphers and Cipher Suites in Windows for a large number (500+ Servers)

We have a large number of servers here (5-700) 2008 and 20012R2 and need to set them to PCI standards. We Can obviously use the IISCrypto tool to  do the setting on a server by server basis but to do this on the large number of remote VMs is painful at best and horribly time consuming. We were able to use registry settings to turn off SSL v3 etc. here but can't see a way to do the same thing for the Ciphers and Cipher SUites. Can anyone suggest a way to do this quickly with a reg file or such? We use a tool called KACE that could deploy or run a batch file etc. Screen capture is attached showing what we need off.
IISCrypto-DisabledCipherSuites.JPG
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Patrick Bogers
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this link have some reg keys to disable RC4
http://windowsitpro.com/windows/disabling-rc4-cipher

I have a reg key to disable RC4 cipher let me check and will post it
1. Open notepad.
2. Paste the below lines:
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 128/128]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40/128]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 56/128]
"Enabled"=dword:00000000

3. Click 'Save As' and select All files below and enter name 'Disable_RC4_Ciphers.reg'

please check before deploying
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THe thought we had was could we USe IISCrypto and Set up one system as needed then export the key as you suggested Patrick. Not sure if that will show the Ciphers or not. We'll try it here and see what it looks like. We WERE able to do that for the SSL items. Might be a day or 3 for results please be patient.
Hi George,

Yes it Will do exactly that (did the same on my platform last year)
Make the change and test that one machine with qualys ssl labs.

Take your time, it is mission critical. Dont forget to backup your registry.....

Cheers
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Thank you will take a look at this tomorrow.
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yes they are. where/how would they be set in GPO? That's something we've never looked at. it sure would make it easy though.
Computer GPO/P security settings/registry is one way to push the registry.
Check advanced templates dealing with security.
https://technet.microsoft.com/en-us/library/cc753092(v=ws.11).aspx

test first on a subset. note usually a GPO takes two loads to apply, in acomputer gpo that might require two reboots ...
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btan

You can look at administrative template for Group Policy
https://github.com/Crosse/SchannelGroupPolicy/blob/master/README.md
Looking at this as well
Ended up using regdiff take before and after snapshots on a clean server with IIScrypto to get the chages as a .reg file we could apply. Patrick that is appropriate.
Thank you for feedback.
If my proposal is appropiate why did you offer all points to btan?
Nice fix! Until Next time.