COMMAND
Carello E-Commerce
SYSTEMS AFFECTED
Carello E-Commerce V1.2.1 for Windows NT
PROBLEM
Following is based on a Defcom Labs Advisory def-2001-25 by Peter
Grundl. A malicious user can execute arbitrary commands on the
E-Commerce server with the privileges of the web server.
The Carello.dll utilizes full physical path to execute Carello
scripts instead of paths relative to the webroot. Some input
validation has been inserted in the program, but not to a
sufficient degree, as can be seen from the following example:
http://foo.org/scripts/Carello/Carello.dll?CARELLOCODE=SITE2&VBEXE=C:\..\winnt\system32\cmd.exe%20/c%20echo%20test>c:\defcom.txt
The example will result in INETINFO.EXE spiking at 100% CPU and
the web server will no longer answer HTTP requests. The
webservice can not be stopped/restarted and the server will need
to be rebooted to regain functionality. The command will be
executed with the privileges of the web server, which, when
dealing with IIS, usually means LocalSystem Access.
The test was performed on a Windows NT 4.0 Server with SP 6a.
SOLUTION
Pacific Software Publishing, Inc. has released version 1.3 to
correct the problem and introduce support for Windows 2000. You
can download it at http://www.carelloweb.com