Mozilla developer Masayuki Nakano discovered that the NativeKey widget continues handling key messages even when it is destroyed by dispatched event listeners. This could result in some key events being applied to other objects or plugins if the widget memory is reallocated to them, leading to a non-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.


External Reference:

http://www.mozilla.org/security/announce/2013/mfsa2013-80.html


Acknowledgements:

Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges Masayuki Nakano  as the original reporter.

Statement:

This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5 and 6