hi chris, i'm not sure what you exactly have read about "security failure with XPCOM", but there have been some articles about security research lately, describing a general weakness in the addon architecture by the lack of isolation between single addons (not all of the articles reflected that super accurately). i would consider this more of a theoretical risk (or a point that should raise awareness for mozilla's addon reviewers), since when you install a malicious addon it can of course perform all these actions directly as well and would not depend on exploiting weaknesses of other extensions. fully reviewed addons you install from addons.mozilla.org can be considered safe imho.

Hi philipp,

I was reading the document in http://www.buyukkayhan.com/publications/ndss2016crossfire.pdf and because using firefox (too) with some add-in, I just wanted to know if there was any way to be sure that the extensions are safe ! Of course I read also the sentence in the mentioned document that say : "we were unable to conduct a detailed scientific study of the attack in practice"

As I'm not a specialist of such extensions I was looking for more informations that the one's available on some internet sites.

Thank you for your help.

Chris