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COMMAND MS Word and MS Access SYSTEMS AFFECTED MS Word and MS Access 2000 (with or without Service Release 1a) PROBLEM Georgi Guninski found following. MS Word and MS Access 2000 (with or without Service Release 1a) allow executing arbitrary programs if a Word document is opened. This may be exploited also by visiting a web page with IE or opening/previewing HTML email message with Outlook. In order this to work, the user must be able to access a mdb file, which resides either on an UNC share or a local drive. This allows taking full control over user's computer. The problem is MS Word accepts an Access database as a data source in Mail Merge. Worse, Word opens the database and executes VBA in forms that are opened at database startup. VBA allows executing arbitrary programs. How to reproduce: 1) Create a db4.mdb file which opens a form at database startup and executes VBA code in the form. 2) Place a copy of db4.mdb in C:\ (for example), you may place it on a UNC share. 3) Open a Word document. 4) Select Tools->Mail Merge->Create->Mailing Labels->New Main Document 5) Select GetData->Open Data Source 6) Choose C:\db4.mdb 7) The rest of the wizard is trivial, you must save the new document. Sample files are available: http://www.nat.bg/~joro/wordaccess.doc http://www.nat.bg/~joro/db4.mdb This is completely different issue from "Georgi Guninski security advisory #14, 2000" "IE 5 and Access 2000 vulnerability - executing programs", which needs IE and ActiveX, while the current bug is in Word/Access. -----------in Form1 of db4.mdb--------------------- Private Sub Form_Load() On Error GoTo Err_Command0_Click Dim stAppName As String stAppName = "C:\Program Files\Accessories\wordpad.exe" MsgBox ("Trying to start: " & stAppName) Call Shell(stAppName, 1) Exit_Command0_Click: Exit Sub Err_Command0_Click: MsgBox Err.Description Resume Exit_Command0_Click End Sub Form1 is automatically opened at database startup. You must have a table in the database. SOLUTION I believe that following covers this issue: http://www.microsoft.com/windows/ie/download/critical/patch11.htm