Firefox Browser Extension Flaw

[silicon_toad2000]

A vulnerability in Firefox's extension structure allows attackers to
execute code under the guise of trusted extensions. The problem is
believed to be the result of Firefox failing to isolate extensions.
Malicious extensions can exploit the situation by operating through the
capabilities of trusted extensions.
http://www.v3.co.uk/v3-uk/news/2453607/millions-of-firefox-users-vulnerable-to-browser-extension-flaw