Medium severity · published Feb 2, 2020
CVE-2020-8516
The daemon in Tor through 0.4.1.8 and 0.4.2.x through 0.4.2.6 does not verify that a rendezvous node is known before attempting to connect to it, which might make it easier for…
5.3
CVSS
2.5%
EPSS
No
On KEV
Description
The daemon in Tor through 0.4.1.8 and 0.4.2.x through 0.4.2.6 does not verify that a rendezvous node is known before attempting to connect to it, which might make it easier for remote attackers to discover circuit information. NOTE: The network team of Tor claims this is an intended behavior and not a vulnerability
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.5% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · Torproject
through 0.4.1.8; 0.4.2.0 through 0.4.2.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-8516
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-8516
Mailing List
https://lists.torproject.org/pipermail/tor-dev/2020-February/014146.html
Mailing List
https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html
Third Party Advisory
https://security-tracker.debian.org/tracker/CVE-2020-8516
Issue Tracking
https://trac.torproject.org/projects/tor/ticket/33129
Exploit
https://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html
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