Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations TouchToneTommy on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Disabled ciphers still functioning?

Status
Not open for further replies.

AkutaSame

Programmer
Oct 5, 2002
97
US
Hello all.

It's been a while since I've had the pleasure of participating on the Tek-tips website; however, I've run into something that is a bit of a bother...

As you can see below, I have taken a few clips from the registry (W2k) to give a little more information about what's going on:

-------------
Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC2 40/128
Class Name: <NO CLASS>
Last Write Time: 2/16/2009 - 10:35 AM
Value 0
Name: Enabled
Type: REG_DWORD
Data: 0x0


Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Ciphers\RC4 40/128
Class Name: <NO CLASS>
Last Write Time: 2/16/2009 - 10:35 AM
Value 0
Name: Enabled
Type: REG_DWORD
Data: 0x0

And as a test, disabled MD5 altogether:

Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Hashes\MD5
Class Name: <NO CLASS>
Last Write Time: 2/16/2009 - 3:19 PM
Value 0
Name: Enabled
Type: REG_DWORD
Data: 0x0
-----------

As is apparent, the RC2 and RC4 40-bit ciphers are disabled. The problem lies with when I do a scan on the server utilizing several different techniques (from third party to scanning using SSLDigger). It shows that the two 40-bit export protocols are enabled, EXP-RC2-CBC-MD5 & EXP-RC4-MD5.

The question I have is wouldn't these ciphers (EXP-RC2-CBC-MD5 & EXP-RC4-MD5) be tied in with the rest of them? There are no other 40 bit ciphers mentioned in the registry under schannel but the two above that are disabled. I know that unless a cipher is specifically disabled that it is enabled for the system to utilize. So if the 40-bit ciphers are disabled, and I see no record anywhere else of the two ciphers in question having different reg keys, shouldn't they in theory be disabled?

I look forward to the responses. I have included an attached file containing the schannel data in whole for perusal.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top