How Did the FBI Get a Tor User's IP Address?

Polling the internet: what is the best way to de-anonymize a Tor user? Somebody over at the FBI definitely has a method, but they clearly aren’t planning on telling anybody anytime soon.

Motherboard originally reported that the bureau has somehow managed to nab the IP address of an alleged criminal using Tor, short for “The Onion Router,” as part of an ongoing anti-terrorism case. The guy in question, Muhammed Momtaz Al-Azhari, of Tampa, Florida, was charged in 2020 with attempting to provide material support to ISIS. According to the government, Al-Azhari is “an ISIS supporter who planned and attempted to carry out an attack on behalf of that terrorist organization.” Part of the government’s case against Al-Azhari revolves around his use of Tor to make multiple visits to an ISIS-related website prior to the planned attack.

The internet’s well-known portal to the dark web, Tor is supposed to protect your IP address and keep you anonymous as you surf. The browser encrypts a web user’s traffic and then bounces it around through a series of “relays” (also called nodes) to cover up the trail of activity. Still, Tor has been known to have vulnerabilities that can lead to de-anonymization.

All that said, it’s not exactly clear what happened here. Somehow, the government ascertained Al-Azhari’s real IP address—which actually turned out to be his grandma’s IP address because he was staying with her in Riverside, California at the time of his arrest, court documents state. Since Tor should have protected Azhari’s real location and IP address, the question remains: how did the feds get this information?

https://news.yahoo.com/did-fbi-tor-users-ip-190400000.html