"Since at least 2017, a mysterious threat actor has run thousands of malicious servers in entry, middle, and exit positions of the Tor network in what a security researcher has described as an attempt to deanonymize Tor users. [...] at one point, there was a 16% chance that a Tor user would connect to the Tor network through one of KAX17’s servers, a 35% chance they would pass through one of its middle relays, and up to 5% chance to exit through one."

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