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- Date: Wed, 31 Mar 1999 16:50:13 +0100
- From: JJ Gray <nexus@PATROL.I-WAY.CO.UK>
- To: BUGTRAQ@netspace.org
- Subject: Potential vulnerability in SCO TermVision Windows 95 client
-
-
- Hi folks,
- I recently downloaded a trial version of the SCO TermVision
- terminal emulation package for SCO Openserver 5 and Windows 95 (
- http://www.sco.com/vision/products/termvision/ ). This comes
- in two parts, the server based binaries and the Windows 95 client,
- TermVision 2.1. In addition to the terminal emulation you get
- 'UNIX Neighborhood' which once supplied with a hostname, username &
- password gives an explorer/X-Windows style interface to the SCO server.
- In the default configuration the hostnames, usernames & passwords are
- saved in a file : C:\Windows\Profiles\%username%\Application
- Data\SCO\Vision\Auth\%username%.vca
- ( PC is Windows 95, NT4 server, user profiles ). The data is encrypted
- but, not being a cryptanalysist, it took me a good 15 minutes to
- discover the encryption is nothing more than a fixed string XOR :(
- I informed SCO of this on 30th March and received a reply the next day :)
- --
- >From Matthew Schofield, Support <mattsc@sco.com>
-
- JJ,
-
- Thanks for highlighting this issue in the Vision Comms.
-
- By your own definition it is insecure, in that the contents of the .vca
- files can be obtained with some effort. In terms of actually using
- someone's .vca file through the comms layer in order to access the UNIX
- resources through a Vision product, the files can only read by the
- comms layer if the user has successfully logged into Windows as that user.
- --
- Extracted from my reply -
-
- This is of no consequence. The point is that I can extract the UNIX
- username & password from another user that has used the same PC.
- If that user happens to use root access then I have the root password -
- thus a non privileged user with windows access can gain root privs on
- the UNIX box, whether through UNIX Neighborhood, terminal emulation,
- a terminal itself, telnet etc. If I were a windows user with no user
- account on the UNIX box......... :)
- --
- When adding a host, the security options can be set to 'Prompt' where the
- password is not saved. Yes this is only a potential security hole -
- another on the 'Configuration' issue, but it is not obvious that this
- vulnerability exists. The default is insecure and there is no 'obvious'
- information in the documentation that it is so - hence my post.
- Matthew finished by saying
- --
- As you have already identified, you should change the password mechanism
- for your host to prompt. In a future release we intend to either change
- the operation of the password mechanism or add an appropriate warning.
- --
- Can't really say fairer than that I suppose...
-
- Regards,
- JJ Gray
-
-
- Sed quis custodiet ipsos custodes ?
-
-