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Mozilla Foundation Security Advisory 2014-69

Uninitialized memory use during GIF rendering

Announced
September 2, 2014
Reporter
Michal Zalewski
Impact
High
Products
Firefox, Firefox ESR, SeaMonkey, Thunderbird
Fixed in
  • Firefox 32
  • Firefox ESR 31.1
  • SeaMonkey 2.29
  • Thunderbird 31.1

Description

Google security researcher Michal Zalewski discovered that when a malformated GIF image is rendered in certain circumstances, memory is not properly initialized before use. The resulting image then uses this memory during rendering. This could allow for the a script in web content to access this unitialized memory using the <canvas> feature.

References