Tor Project and Mozilla are working together to improve the security of Tor users. Improvements aim to block malware from trying to gather information to unmask users. The Tor Browser is composed of two components, a modified version of the Firefox browser, and the Tor proxy which implements routing functionalities in the Tor network. An attacker can try to hack the browser component forcing it to connect to other than the legitimate Tor proxy part, for example, a server set up by the attacker that gathers user data.”]
Source: https://securityaffairs.co/wordpress/52249/deep-web/tor-project-improvements.html