COMMAND
kernel
SYSTEMS AFFECTED
Win2000
PROBLEM
Following is based on a Microsoft Security Bulletin (MS00-069).
Input Method Editors (IMEs) enable character-based languages such
as Chinese to be entered via a standard 101-key keyboard. When an
IME is installed as part of the system setup, it is available by
default as part of the logon screen. In such a case, the IME
should recognize that it is running in the context of the
LocalSystem and not in the context of a user, and restrict
certain functions. However, the IME for Simplified Chinese does
not correctly recognize the machine state, and exposes
inappropriate functions as part of the logon screen. As a result,
a malicious user who had access to either a physical keyboard or a
terminal server session on an affected machine could gain
LocalSystem privilege even without logging onto the machine.
This vulnerability only affects the Simplified Chinese version of
Windows 2000 by default - customers using any other version of
Windows 2000 are not affected. Even if the Simplified Chinese
IMEs were installed after setup as part of a language pack, it
would not be present as part of the logon screen and therefore
would not pose a security threat. The vulnerability allows only
the local machine to be compromised, but does not grant any
domain privileges (unless, of course, the local machine happens
to be a domain controller). Because the vulnerability is exposed
as part of the logon screen, it could only be exploited by a user
who had physical access to a keyboard, or who could start a
terminal server session on an affected machine. If best practices
- which strongly recommend against giving normal users physical
access to critical servers, or allowing terminal server session
on such servers - have been followed, this vulnerability would
affect only workstations and terminal servers.
Customers running any other language version of Windows 2000 only
need to take action if they installed a Simplified Chinese IME
during system setup.
SOLUTION
Patch availability:
- Microsoft Windows 2000, Simplified Chinese version: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=24631
- Microsoft Windows 2000, English version: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=24627
This patch can be installed on systems running Windows 2000,
either with or without Service Pack 1. The patch will be
incorporated into Service Pack 2.