Security researcher regenrecht reported, via TippingPoint's Zero Day Initiative, a use-after-free using the domDoc pointer within Vibrate library. This can lead to arbitrary code execution when exploited. In general these flaws cannot be exploited through email in the Thunderbird and SeaMonkey products because scripting is disabled, but are potentially a risk in browser or browser-like contexts in those products. External Reference: http://www.mozilla.org/security/announce/2013/mfsa2013-18.html Acknowledgements: Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges regenrecht as the original reporter. Statement: Not Vulnerable. This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5 and 6