CVE-2021-39246

Public Exploit

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).

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory torproject.org Vendor Advisory torproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/sickcodes/security/blob/master/advisories/SICK-2021-111.md third party advisory exploit
https://sick.codes/sick-2021-111 third party advisory exploit
https://www.privacyaffairs.com/cve-2021-39246-tor-vulnerability third party advisory
https://gitlab.torproject.org/tpo/core/tor/-/commit/80c404c4b79f3bcba3fc4585d4c62a62a04f3ed9 patch vendor advisory
https://gitlab.torproject.org/tpo/core/tor/-/merge_requests/434 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-39246?
CVE-2021-39246 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39246?
To fix CVE-2021-39246, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39246 being actively exploited in the wild?
It is possible that CVE-2021-39246 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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