24th Jan 2003 [SBWID-5949]
Windows 2000 Terminal Server DoS attack
Windows 2000 Terminal Server
Jonathan Hunter says :
Any user with sufficient permission to log on to a Windows 2000
Terminal Server (via RDP or ICA) and access its filesystem can reboot
the server at will.
- Open %SYSTEMROOT%\SYSTEM32\MSGINA.DLL for exclusive access (read lock).
I used Radsoft's HEXVIEW.EXE from Rix2K to do this.
- Open a new connection to the server via RDP/ICA
- Click the nice, helpful "Restart" button in the warning dialog that
appears ("msgina.dll failed to load")
Tested on Windows 2000 Server (IE55, SP2) and Windows 2000 Server
no patch yet.
- Remove all permissions from MSGINA.DLL for "Power Users", "Users" and
Note: The above workaround has been tested on Windows 2000 Server
(IE55, SP2) and users were still able to log in as normal. I am not
aware of a need for MSGINA.DLL to be accessible by normal users, but if
there are any such circumstances Microsoft will need to produce an