Mozilla Foundation Security Advisory 2013-59

XrayWrappers can be bypassed to run user defined methods in a privileged context

Announced
June 25, 2013
Reporter
moz_bug_r_a4
Impact
High
Products
Firefox, Firefox ESR, SeaMonkey, Thunderbird, Thunderbird ESR
Fixed in
  • Firefox 22
  • Firefox ESR 17.0.7
  • SeaMonkey 2.19
  • Thunderbird 17.0.7
  • Thunderbird ESR 17.0.7

Description

Mozilla security researcher moz_bug_r_a4 reported that XrayWrappers can be bypassed to call content-defined toString and valueOf methods through DefaultValue. This can lead to unexpected behavior when privileged code acts on the incorrect values.

In general these flaws cannot be exploited through email in the Thunderbird and SeaMonkey products because scripting is disabled, but are potentially a risk in browser or browser-like contexts in those products.

References