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Mozilla Foundation Security Advisory 2013-79

Use-after-free in Animation Manager during stylesheet cloning

September 17, 2013
Abhishek Arya
Firefox, Firefox ESR, SeaMonkey, Thunderbird, Thunderbird ESR
Fixed in
  • Firefox 24
  • Firefox ESR 17.0.9
  • SeaMonkey 2.21
  • Thunderbird 24
  • Thunderbird ESR 17.0.9


Security researcher Abhishek Arya (Inferno) of the Google Chrome Security Team used the Address Sanitizer tool to discover a use-after-free problem in the Animation Manager during the cloning of stylesheets. This can lead 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.