Security researcher Mariusz Mlynski reported that the location
property can be accessed by binary plugins through top.location
with a frame whose name attribute's value is set to "top". This can allow for possible cross-site scripting (XSS) attacks through plugins.
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.