This paper discusses a number of ways through which hackers can use Mozilla Firefox as a platform to run there malicious pieces of code with privileges and features.
You can download it from the following link: https://packetstormsecurity.com/files/download/120512/Abusing_Exploiting_and_Pwning_with_Firefox_Add-ons_final_dec.pdf
Source: https://packetstormsecurity.com/files/120512/Abusing-Exploiting-And-Pwning-With-Firefox-Add-Ons.html