CVE-2021-39246: Medium severity torproject Tor Browser vulnerability

Published Sep 24, 2021
·
Updated

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).

Affected Software

12 affected components
torproject Tor Browser<=10.5.6
torproject Tor Browser=11.0-alpha2
torproject Tor Browser=11.0-alpha4
Apple macOS
Linux Linux kernel
Microsoft Windows
All of the following
Any of the following
torproject Tor Browser<=10.5.6
torproject Tor Browser=11.0-alpha2
torproject Tor Browser=11.0-alpha4
Any of the following
Apple macOS
Linux Linux kernel
Microsoft Windows

Event History

Sep 24, 2021
CVE Published
via MITRE·06:08 PM
Data Sourced
via MITRE·06:08 PM
Description
Data Sourced
via NVD·07:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-39246?

CVE-2021-39246 is a vulnerability in Tor Browser versions 10.5.6 and 11.x through 11.0a4 that allows a correlation attack compromising the privacy of visits to v2 onion addresses.

2

How does CVE-2021-39246 affect Tor Browser?

CVE-2021-39246 affects Tor Browser versions 10.5.6 and 11.x through 11.0a4 by enabling a correlation attack that compromises the privacy of visits to v2 onion addresses.

3

What is the severity of CVE-2021-39246?

The severity of CVE-2021-39246 is medium with a CVSS score of 6.1.

4

How can CVE-2021-39246 be exploited?

CVE-2021-39246 can be exploited by an attacker comparing exact timestamps of locally logged onion-service visits to timestamp data collected by the destination.

5

Is Apple macOS or Linux Linux kernel affected by CVE-2021-39246?

No, Apple macOS and Linux Linux kernel are not affected by CVE-2021-39246.

Contact

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