Security researcher Ronald Crane reported an underflow found through code inspection. This does not all have a clear mechanism to be exploited through web content but could be vulnerable if a means can be found to trigger it.


External Reference:

https://www.mozilla.org/security/announce/2015/mfsa2015-145.html


Acknowledgements:

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