Mozilla Foundation Security Advisory 2010-76

Chrome privilege escalation with window.open and <isindex> element

Announced
December 9, 2010
Reporter
echo
Impact
Critical
Products
Firefox, SeaMonkey
Fixed in
  • Firefox 3.5.16
  • Firefox 3.6.13
  • SeaMonkey 2.0.11

Description

Security researcher echo reported that a web page could open a window with an about:blank location and then inject an <isindex> element into that page which upon submission would redirect to a chrome: document. The effect of this defect was that the original page would wind up with a reference to a chrome-privileged object, the opened window, which could be leveraged for privilege escalation attacks.

Mozilla security researcher moz_bug_r_a4 provided proof-of-concept code demonstrating how the above vulnerability could be used to run arbitrary code with chrome privileges.

References