Georgi Guninski security advisory #7, 2000 Wordpad vulnerability, exploitable also in IE for Win9x Disclaimer: The opinions expressed in this advisory and program are my own and not of any company. The usual standard disclaimer applies, especially the fact that Georgi Guninski is not liable for any damages caused by direct or indirect use of the information or functionality provided by this program. Georgi Guninski, bears NO responsibility for content or misuse of this program or any derivatives thereof. Description: There is a vulnerability in Wordpad which allows executing arbitrary programs without warning the user after activating an embedded or linked object. This may be also exploited in IE for Win9x. Details: Wordpad executes programs embeded in .doc or .rtf documents without any warning if the object is activated by doubleclick. This may be exploited in IE for Win9x using the view-source: protocol. The view-source: protocol starts Notepad, but if the file is large, then the user is asked to use Wordpad. So creating a large .rtf document and creating a HTML view-source: link to it in a HTML page or HTML based email message will prompt the user to use Wordpad and a program may be executed if the user doubleclicks on an object in the opened document. Demonstration which starts AUTOEXEC.BAT: http://www.whitehats.com/guninski/wordpad1.html Workaround: Do not activate objects in Wordpad documents Copyright Georgi Guninski Regards, Georgi Guninski http://www.nat.bg/~joro