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COMMAND IE/Outlook Express SYSTEMS AFFECTED IE 5.5/Outlook Express Patched IE 6.0, somewhat patched 5.5 Win2K PROBLEM Following is based on a Georgi Guninski security advisory #22. Internet Explorer 5.5/Outlook Express/(probably Outlook if Active Scripting is enabled) under Windows 98/2000 (suppose all other versions are also vulnerable) allow reading local and UNC files. The problem is the GetObject() JScript function and the \"htmlfile\" ActiveX object. A call a=GetObject(\"c:\\test.txt\",\"htmlfile\") creates a HTML document object with full access to its DOM. Examine the code for details. The code is: ------getobject1.html-------------------------------- <SCRIPT> alert(\"This script reads C:\\TEST.TXTnYou may need to create it\"); a=GetObject(\"c:\\test.txt\",\"htmlfile\"); setTimeout(\"alert(a.body.innerText);\",2000); </SCRIPT> ----------------------------------------------------- Demonstration is available at: http://www.guninski.com/getobject1.html Just a quick note: if you have configured explorer so that it asks you before executing ActiveX, it will prompt you before executing the above script. Tested on IE5.0/Win2000. Update ====== If you replace the function with a=GetObject(\"http://\"+location.host+\"/../../../../../../test.txt\",\"htmlfile\"); latest version (IE6.0) is still vulnerable SOLUTION Disable Active Scripting.