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Mozilla Foundation Security Advisory 2014-87

Use-after-free during HTML5 parsing

Announced
December 2, 2014
Reporter
SkyLined
Impact
Critical
Products
Firefox, Firefox ESR, Firefox OS, SeaMonkey, Thunderbird
Fixed in
  • Firefox 34
  • Firefox ESR 31.3
  • Firefox OS 2.2
  • SeaMonkey 2.31
  • Thunderbird 31.3

Description

Security researcher SkyLined reported a use-after-free created by triggering the creation of a second root element while parsing HTML written to a document created with document.open(). This leads to a potentially exploitable crash.

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

References