Security researcher Cody Crews reported a mechanism to use the cloneNode method to bypass System Only Wrappers (SOW) and clone a protected node. This allows violation of the browser's same origin policy and could also lead to privilege escalation and the execution of arbitrary code.
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