Mozilla Foundation Security Advisory 2014-28

SVG filters information disclosure through feDisplacementMap

Announced
March 18, 2014
Reporter
Robert O'Callahan
Impact
High
Products
Firefox, Firefox ESR, SeaMonkey, Thunderbird
Fixed in
  • Firefox 28
  • Firefox ESR 24.4
  • SeaMonkey 2.25
  • Thunderbird 24.4

Description

Mozilla developer Robert O'Callahan reported a mechanism for timing attacks involving SVG filters and displacements input to feDisplacementMap. This allows displacements to potentially be correlated with values derived from content. This is similar to the previously reported techniques used for SVG timing attacks and could allow for text values to be read across domains, leading to information disclosure.

In general this flaw cannot be exploited through email in the Thunderbird and Seamonkey products because scripting is disabled, but is potentially a risk in browser or browser-like contexts.

References