Security researcher regenrecht reported, via TippingPoint's Zero Day Initiative, a use-after-free within the ListenerManager when garbage collection is forced after data in listener objects have been allocated in some circumstances. This results in a use-after-free which can lead to arbitrary code execution.
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.
Vulmon