At the SecurityByte & OWASP AppSec Conference in India, Roberto Suggi Liverani and Nick Freeman offered insight into the substantial danger posed by Firefox extensions. Mozilla doesn t have a security model for extensions and Firefox fullytrusts the code of the extensions. There are no security boundaries between extensions and, to make things even worse, an extension can.silently modify another extension. Read the full article in this article by Nick Freeman at http://www.mailonline.co.uk/news/newsinform.
Source: https://threatpost.com/dangers-firefox-extensions-112009/73146/