Firefox 2.0.0.5 Update -- Fast Work on Reported Exploit!

Last week, a highly critical risk was reported, with proof of concept, involving registering a "firefoxurl://" URI (uniform resource identifier) handler on a computer with both IE and Firefox 2.0 (or later). This was described by Mozillazine as follows:

"When installed on Windows, Firefox registers a URL protocol handler to handle firefoxurl:// URLs (this works much like a http:// or ftp:// URL protocol handler). If an IE user visits a webpage that tries to call a firefoxurl:// URL (for example, using an iframe), IE will launch Firefox with no further prompting, passing it the URL. Neither IE nor Firefox escape or sanitise the URL, which allows an attacker to inject additional parameters into the command line used to invoke Firefox. Used in combination with the -chrome parameter, the attacker can make Firefox execute dangerous JavaScript code."

If you read the above-referenced Mozillazine article, note the finger pointing as to whether the problem is caused by IE for passing untrusted data to another application or by Firefox for not validating input properly. Regardless of where the problem resides, Mozilla reacted quickly and included the fix in Firefox 2.0.0.5.

Note: By default, Firefox automatically checks for updates. If you have changed that setting, go to Menu > Help > Check for updates.


Included in Firefox 2.0.0.5:

• MFSA 2007-25 XPCNativeWrapper pollution
• MFSA 2007-24 Unauthorized access to wyciwyg:// documents
• MFSA 2007-23 Remote code execution by launching Firefox from Internet Explorer
• MFSA 2007-22 File type confusion due to %00 in name
• MFSA 2007-21 Privilege escalation using an event handler attached to an element not in the document
• MFSA 2007-20 Frame spoofing while window is loading
• MFSA 2007-19 XSS using addEventListener and setTimeout
• MFSA 2007-18 Crashes with evidence of memory corruption
  

References:

• Firefox Download Page
• Release Notes

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