A zero-day exploit in the FireFox browser is in the wild that is used by hackers to de-anonymize people who are using Tor by executing malicious code on the victim’s machine. However, the overall internet users using FireFox browser are vulnerable to this zero-day exploit.
Roger Dingledine, Tor co-founder, confirmed the news of zero-day exploit and announced that Mozilla security team is working on this to fix the bug.
The zero-day is a corrupting memory vulnerability that exploits and executes malicious code on Windows operating systems.
A security research Raylee explained that exploit is quite similar to the one that was used by law enforcements in 2013 to expose the users of illicit material serving site hosted on Freedom Hosting.
“It’s almost the same as the payload used in 2013,” Raylee told ArsTechnicia. “It exploits some vulnerability that executes code very similar to that used in the 2013 Tor browser exploit. Most of the code is identical; just small parts have changed.”
The zero-day exploit code can target various versions of Firefox browser from version 41 to 50; the exploit can target all these versions which mean that attackers have enhanced their malicious code over time.