CVE-2020-8516

Name	CVE-2020-8516
Description	DISPUTED 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.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
NVD severity	medium

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
tor (PTS)	stretch	0.2.9.16-1	vulnerable
	stretch (security)	0.2.9.15-1	vulnerable
	buster, buster (security)	0.3.5.16-1	vulnerable
	bullseye, bullseye (security)	0.4.5.10-1~deb11u1	vulnerable
	bookworm, sid	0.4.6.9-1	vulnerable

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
tor	source	(unstable)	(unfixed)	unimportant

Notes

Not considered a bug / explicit design choice by upstream
https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html
https://trac.torproject.org/projects/tor/ticket/33129
http://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html