Security researcher David Bloom of Cue discovered that <select> elements are always-on-top chromeless windows and that navigation away from a page with an active <select> menu does not remove this window.When another menu is opened programmatically on a new page, the original <select> menu can be retained and arbitrary HTML content within it rendered, allowing an attacker to cover arbitrary portions of the new page through absolute positioning/scrolling, leading to spoofing attacks. Security researcher Jordi Chancel found a variation that would allow for click-jacking attacks was well.
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.
Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges David Bloom of Cue as the original reporter.
Common Vulnerabilities and Exposures assigned an identifier CVE-2012-5354 to
the following vulnerability:
Mozilla Firefox before 16.0, Thunderbird before 16.0, and SeaMonkey
before 2.13 do not properly handle navigation away from a web page
that has multiple menus of SELECT elements active, which allows remote
attackers to conduct clickjacking attacks via vectors involving an XPI
file, the window.open method, and the Geolocation API, a different
vulnerability than CVE-2012-3984.
(This is a new one that MITRE assigned)
Not vulnerable. This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5 and 6.