Correlation Attack Vulnerability in Tor Browser: Compromising Privacy of v2 Onion Addresses

CVE-2021-39246 · MEDIUM Severity

CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Tor Browser through 10.5.6 and 11.x through 11.0a4 allows a correlation attack that can compromise the privacy of visits to v2 onion addresses. Exact timestamps of these onion-service visits are logged locally, and an attacker might be able to compare them to timestamp data collected by the destination server (or collected by a rogue site within the Tor network).

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