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COMMAND Frame Domain Verification, Unauthorized Cookie Access and Malformed Component Attribute SYSTEMS AFFECTED Microsoft Internet Explorer 4.0, 4.01, 5.0 and 5.01 PROBLEM Following is a based on a Security Bulletin from the Microsoft. The three security vulnerabilities eliminated by this patch are unrelated to each other except by the fact that they all occur in the same .dll. We have packaged them together for customer convenience. The vulnerabilities are: - \"Frame Domain Verification\" vulnerability. When a web server opens a frame within a window, the IE security model should only allow the parent window to access the data in the frame if they are in the same domain. However, two functions available in IE do not properly perform domain checking, with the result that the parent window could open a frame that contains a file on the local computer, then read it. This could allow a malicious web site operator to view files on the computer of a visiting user. The web site operator would need to know (or guess) the name and location of the file, and could only view file types that can be opened in a browser window. This was reported by Mead & Company\'s Andrew Nosenko. - \"Unauthorized Cookie Access\" vulnerability. By design, the IE security model restricts cookies so that they can be read only by sites within the originator\'s domain. However, by using a specially-malformed URL, it is possible for a malicious web site operator to gain access to another site\'s cookie and read, add or change them. A malicious web site operator would need to entice a visiting user into clicking a link in order to access each cookie, and could not obtain a listing of the cookies available on the visitor\'s system. Even after recovering a cookie, the type and amount of personal information would depend on the privacy practices followed by the site that placed it there. This was reported by Marc Slemko. Update ====== Sample exploit : http://passport.com%20.sub.znep.com/cgi-bin/cookies ...will cause IE to connect to the hostname specified, but send the cookies to the server based on the hostname before the \"%20\", in this case passport.com. The \"%20\" is the URL encoded version of a space character. \"%20\" isn\'t the only character that works, there are a variety of others that are also misparsed. However secure cookies dosen\'t seemed vulnerable. ====== More details on : [http://alive.znep.com/~marcs/security/iecookie2/] - \"Malformed Component Attribute\" vulnerability. The code used to invoke ActiveX components in IE has an unchecked buffer and could be exploited by a malicious web site operator to run code on the computer of a visiting user. The unchecked buffer is only exposed when certain attributes are specified in conjunction with each other. This was reported by UNYUN, the Shadow Penguin Security Research Group of Japan. SOLUTION Patch availability: http://www.microsoft.com/windows/ie/download/critical/patch6.htm http://www.microsoft.com/technet/security/bulletin/ms01-055.asp http://www.microsoft.com/windows/ie/downloads/critical/q312461/default.asp The patches require IE 4.01 Service Pack 2 or IE 5.01 to install. Customers using versions prior to these may receive a message reading \"This update does not need to be installed on this system\". This message is incorrect. More information is available in KB article Q262509. The patch also eliminates a new variant of the previously addressed WPAD Spoofing vulnerability