{"id":"CVE-2020-8516","aliases":["DEBIAN-CVE-2020-8516","EUVD-2020-29382","GHSA-gvvc-pv9r-rg5q"],"status":"disputed","title":"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...","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","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.02499,"percentile":0.84831,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-200"],"published":"2020-02-02T12:52:56Z","modified":"2026-10-26T12:02:24Z","affected":[{"source":"osv","ecosystem":"Debian:12","package":"tor","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.7.13-1","0.4.7.16-1","0.4.8.10-1","0.4.8.10-1~bpo11+1","0.4.8.10-1~bpo12+1","0.4.8.11-1","0.4.8.11-1~bpo11+1","0.4.8.11-1~bpo12+1","0.4.8.12-1","0.4.8.12-1.1","0.4.8.12-1~bpo11+1","0.4.8.12-1~bpo12+1","0.4.8.13-1","0.4.8.13-2","0.4.8.13-2~bpo12+1","0.4.8.14-1","0.4.8.14-1~bpo12+1","0.4.8.16-1","0.4.8.21-1","0.4.8.21-1~bpo12+1","0.4.8.21-1~bpo13+1","0.4.8.21-1~bpo13+2","0.4.8.22-1","0.4.8.22-1~bpo12+1","0.4.8.22-1~bpo13+1","0.4.8.4-2","0.4.8.5-1","0.4.8.6-1","0.4.8.7-1","0.4.8.8-1","0.4.8.9-1","0.4.8.9-1~bpo11+1","0.4.8.9-1~bpo12+1","0.4.9.11-0+deb12u1","0.4.9.11-1","0.4.9.11-1~bpo13+1","0.4.9.12-2","0.4.9.12-3","0.4.9.12-4","0.4.9.13-1","0.4.9.14-1","0.4.9.5-1","0.4.9.5-2","0.4.9.5-2~bpo12+1","0.4.9.5-2~bpo13+1","0.4.9.6-0+deb12u1","0.4.9.6-1","0.4.9.6-1~bpo12+1","0.4.9.6-1~bpo13+1","0.4.9.8-0+deb12u1","0.4.9.8-1","0.4.9.8-1~bpo12+1","0.4.9.8-1~bpo13+1","0.4.9.9-1","0.4.9.9-1~bpo13+1"]},{"source":"osv","ecosystem":"Debian:13","package":"tor","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.8.16-1","0.4.8.21-1","0.4.8.21-1~bpo12+1","0.4.8.21-1~bpo13+1","0.4.8.21-1~bpo13+2","0.4.8.22-1","0.4.8.22-1~bpo12+1","0.4.8.22-1~bpo13+1","0.4.9.11-0+deb13u1","0.4.9.11-1","0.4.9.11-1~bpo13+1","0.4.9.12-0+deb13u1","0.4.9.12-0+deb13u2","0.4.9.12-2","0.4.9.12-3","0.4.9.12-4","0.4.9.13-0+deb13u1","0.4.9.13-1","0.4.9.14-0+deb13u1","0.4.9.14-1","0.4.9.5-1","0.4.9.5-2","0.4.9.5-2~bpo12+1","0.4.9.5-2~bpo13+1","0.4.9.6-0+deb13u1","0.4.9.6-1","0.4.9.6-1~bpo12+1","0.4.9.6-1~bpo13+1","0.4.9.8-0+deb13u1","0.4.9.8-1","0.4.9.8-1~bpo12+1","0.4.9.8-1~bpo13+1","0.4.9.9-1","0.4.9.9-1~bpo13+1"]},{"source":"osv","ecosystem":"Debian:14","package":"tor","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.4.8.16-1","0.4.8.21-1","0.4.8.21-1~bpo12+1","0.4.8.21-1~bpo13+1","0.4.8.21-1~bpo13+2","0.4.8.22-1","0.4.8.22-1~bpo12+1","0.4.8.22-1~bpo13+1","0.4.9.11-1","0.4.9.11-1~bpo13+1","0.4.9.12-2","0.4.9.12-3","0.4.9.12-4","0.4.9.13-1","0.4.9.14-1","0.4.9.5-1","0.4.9.5-2","0.4.9.5-2~bpo12+1","0.4.9.5-2~bpo13+1","0.4.9.6-1","0.4.9.6-1~bpo12+1","0.4.9.6-1~bpo13+1","0.4.9.8-1","0.4.9.8-1~bpo12+1","0.4.9.8-1~bpo13+1","0.4.9.9-1","0.4.9.9-1~bpo13+1"]}],"products":[{"vendor":"torproject","product":"tor"}],"references":[{"url":"https://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html","tags":["x_refsource_MISC","x_transferred","Exploit","Mitigation","Technical Description","Third Party Advisory","evidence"]},{"url":"https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html","tags":["x_refsource_MISC","x_transferred","Mailing List","Vendor Advisory","advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2020-8516","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory"]},{"url":"https://lists.torproject.org/pipermail/tor-dev/2020-February/014146.html","tags":["x_refsource_MISC","x_transferred","Mailing List","Vendor Advisory","advisory"]},{"url":"https://trac.torproject.org/projects/tor/ticket/33129","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Vendor Advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-8516"},{"url":"https://github.com/advisories/GHSA-gvvc-pv9r-rg5q"}],"sources":{"cve":[{"id":"CVE-2020-8516","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","status":"disputed","published":"2020-02-02T12:52:56Z","modified":"2024-08-04T10:03:45.879Z","updated_at":"2026-11-02T14:35:50.88562Z"}],"euvd":[{"id":"EUVD-2020-29382","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","status":"published","published":"2020-02-02T12:52:56Z","modified":"2024-08-04T10:03:45Z","updated_at":"2026-11-03T03:07:57.14802Z"}],"ghsa":[{"id":"GHSA-gvvc-pv9r-rg5q","title":"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...","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.","status":"published","published":"2022-05-24T17:07:52Z","modified":"2023-01-29T05:01:17Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-200"],"updated_at":"2026-11-02T14:44:46.934337Z"}],"nvd":[{"id":"CVE-2020-8516","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","status":"disputed","published":"2020-02-02T13:15:10.903Z","modified":"2026-06-17T03:26:30.22Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:05:53.837808Z"}],"osv":[{"id":"CVE-2020-8516","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","status":"published","published":"2020-02-02T13:15:10.903Z","modified":"2026-10-24T10:30:30.878590749Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:17.663289Z"},{"id":"DEBIAN-CVE-2020-8516","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","status":"published","published":"2020-02-02T13:15:10.903Z","modified":"2026-10-26T12:02:24.260904519Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:34.311861Z"}]}}