Vulnerabilities in an ActiveX control distributed with Internet Explorer 5 and available for Internet Explorer 4 allow malicous web sites to steal local files and to bypass cross-frame security rules.
The DHTML Edit Control Safe for Scripting ActiveX control allows web authors and application developers to add WYSIWYG DHTML editing capabilities to thier web sites and applications.
The control allows the web site to upload any data entered into the control. A vulnerability in the control allows malicious web site operators to instruct the control to upload a specific file if they known its pathname.
Another vulnerability in this controls also allows local files to be stolen by using redirection. When a malicious web server sends a redirect to an HTTP request made by the control, its location property will still contain the requested url but will instead display the redirected url, including local URLs such as 'file://c:/config.sys'. The contents of the control can then be acessed (using dh.DOM.body.innerText) and be uploaded to the web server.
Another vulnerability in this control allows an HTML document to acess the contents (read and write) of other framers regardless of their domain of origin against the cross-frame security rules. It also allows the page to perform spoofed transactions allowing it to submit forms without user intervention.