CVE-2021-39246

medium
New! CVE Severity Now Using CVSS v3

The calculated severity for CVEs has been updated to use CVSS v3 by default. CVEs that do not have a CVSS v3 score will fall back CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Description

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).

References

https://sick.codes/sick-2021-111

https://gitlab.torproject.org/tpo/core/tor/-/commit/80c404c4b79f3bcba3fc4585d4c62a62a04f3ed9

https://www.privacyaffairs.com/cve-2021-39246-tor-vulnerability

https://gitlab.torproject.org/tpo/core/tor/-/merge_requests/434

https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-111.md

Details

Source: MITRE

Published: 2021-09-24

Updated: 2021-10-01

Type: CWE-532

Risk Information

CVSS v2

Base Score: 3.6

Vector: AV:L/AC:L/Au:N/C:P/I:P/A:N

Impact Score: 4.9

Exploitability Score: 3.9

Severity: LOW

CVSS v3

Base Score: 6.1

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

Impact Score: 5.2

Exploitability Score: 0.9

Severity: MEDIUM