Mozilla Foundation Security Advisory 2012-100

Improper security filtering for cross-origin wrappers

Announced
November 20, 2012
Reporter
Bobby Holley
Impact
High
Products
Firefox, Firefox ESR, SeaMonkey, Thunderbird, Thunderbird ESR
Fixed in
  • Firefox 17
  • Firefox ESR 10.0.11
  • SeaMonkey 2.14
  • Thunderbird 17
  • Thunderbird ESR 10.0.11

Description

Mozilla developer Bobby Holley reported that security wrappers filter at the time of property access, but once a function is returned, the caller can use this function without further security checks. This affects cross-origin wrappers, allowing for write actions on objects when only read actions should be properly allowed. This can lead to cross-site scripting (XSS) attacks.

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