Mozilla Foundation Security Advisory 2011-38
XSS via plugins and shadowed window.location object
- Announced
- September 27, 2011
- Reporter
- Boris Zbarsky
- Impact
- High
- Products
- Firefox, SeaMonkey, Thunderbird
- Fixed in
-
- Firefox 3.6.23
- Firefox 6
- SeaMonkey 2.3
- Thunderbird 3.1.15
- Thunderbird 6
Description
Mozilla developer Boris Zbarsky reported that a frame
named "location" could shadow the window.location
object unless a
script in a page grabbed a reference to the true object before the frame
was created. Because some plugins use the value of window.location to determine
the page origin this could fool the plugin into granting the plugin content
access to another site or the local file system in violation of the Same Origin
Policy. This flaw allows circumvention of the fix added for
MFSA 2010-10.