There are a lot of questions here that require answers from the developers. This would not only protect against simple JS exploits but also vulnerabilities in the HTML or image file rendering code. The real solution however would be to add some level of sandboxing (be that built into the browser, the OS like MIC, Apparmor, SeLinux or seatbelt or through a 3rd party standalone application like a VM or sandboxie). NoScript white-list consisting of only https domains would be a better default and still offer a reasonable user-experience.

Add the lack of auto updating (all you get is a warning/notice on the default homepage) and I'm sure a good portion of Tor users is vulnerable because of this decision. The window of several days between the upstream release of security patches for Firefox and TBB releases doesn't help. Every JavaScript related code execution vulnerability can be used not only to fully compromise browser sessions, saved cookies, history and passwords but your entire user account on your OS, all files and most importantly, your IP address! Of course it's the wrong decision, especially since Firefox doesn't do sandboxing like Chrome, IE and now Safari. It has been brought up before but the developers think it's a good idea. Additional screenshots of this application download may be available, too.Same with the Linux bundle since several versions. Virus and Malware Tests: For security reasons, you should also check out the Tor Browser download at which includes virus and malware tests. Version 13.0.1 is a freeware program which does not have restrictions and it's free so it doesn't cost anything.

'Onion Routing' refers to the layers of the encryption used. Using Tor makes it more difficult to trace Internet activity, including 'visits to Web sites, online posts, instant messages, and other communication forms', back to the user and is intended to protect the personal privacy of users, as well as their freedom and ability to conduct confidential business by keeping their internet activities from being monitored. Tor directs Internet traffic through a free, worldwide, volunteer network consisting of more than four thousand relays to conceal a user's location or usage from anyone conducting network surveillance or traffic analysis.

Tor Browser screenshot Tor (or The Onion Router) is a free software for enabling online anonymity.

Download Tor 12.5.1