The Tor Project has released Tor Browser 10.0.18 to fix numerous bugs, including a vulnerability that allows sites to track users by fingerprinting the applications installed on their devices. The vulnerability is especially concerning for Tor users who use the browser to protect their identity and IP address from being logged with sites. As this vulnerability tracks users across browsers, it could allow web sites, and even law enforcement, to track a user’s real IP address when they switch to a non-anonymizing browser such as Google Chrome.
Source: https://www.bleepingcomputer.com/news/security/tor-browser-fixes-vulnerability-that-tracks-you-using-installed-apps/