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.
Vulmon