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Mozilla Foundation Security Advisory 2015-134

Miscellaneous memory safety hazards (rv:43.0 / rv:38.5)

December 15, 2015
Mozilla Developers
Firefox, Firefox ESR, Firefox OS, Thunderbird
Fixed in
  • Firefox 43
  • Firefox ESR 38.5
  • Firefox OS 2.5
  • Thunderbird 38.5


Mozilla developers and community identified and fixed several memory safety bugs in the browser engine used in Firefox and other Mozilla-based products. Some of these bugs showed evidence of memory corruption under certain circumstances, and we presume that with enough effort at least some of these could be exploited to run arbitrary code.


Andrei Vaida, Jesse Ruderman, and Bob Clary reported memory safety problems and crashes that affect Firefox ESR 38.4 and Firefox 42.

Christian Holler, Jesse Ruderman, Eric Rahm, Robert Kaiser, Harald Kirschner, and Michael Henretty reported crash and memory safety problems that affect Firefox 42.