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
Published Feb 2, 2020
5.3
MEDIUMCVSS 3.1
EPSS 2.50%
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
Affected products
No data.
- ≤ 0.4.1.8
- ≥ 0.4.2.0 · ≤ 0.4.2.6
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 2.50% (0.02499) | 84.16th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.51% (0.02506) | 82.62th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.80% (0.00803) | 72.43th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.19% (0.00194) | 58.29th | v3 (v2023.03.01) |
| Jan 18, 2024 | 0.19% (0.00194) | 57.34th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.19% (0.00193) | 55.31th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.21% (0.01213) | 66.61th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.21% (0.01213) | 64.21th | v2 (v2022.01.01) |
| Mar 31, 2022 | 7.18% (0.07176) | 80.78th | v2 (v2022.01.01) |
| Jan 6, 2022 | 6.66% (0.06657) | 83.00th | v1 |
| Jan 5, 2022 | 1.57% (0.01565) | 74.03th | v5 (v2026.06.15) |
| Apr 14, 2021 | 1.57% (0.01565) | 0.00th | v1 |
No CWE recorded.
References (5)
- https://lists.torproject.org/pipermail/tor-dev/2020-February/014146.html x_refsource_MISCMailing ListVendor Advisory
- https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html x_refsource_MISCMailing ListVendor Advisory
- https://security-tracker.debian.org/tracker/CVE-2020-8516 x_refsource_MISCThird Party Advisory
- https://trac.torproject.org/projects/tor/ticket/33129 x_refsource_MISCIssue TrackingVendor Advisory
- https://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html x_refsource_MISCExploitMitigationTechnical DescriptionThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| https://lists.torproject.org/pipermail/tor-dev/2020-February/014146.html | x_refsource_MISCMailing ListVendor Advisory | |
| https://lists.torproject.org/pipermail/tor-dev/2020-February/014147.html | x_refsource_MISCMailing ListVendor Advisory | |
| https://security-tracker.debian.org/tracker/CVE-2020-8516 | x_refsource_MISCThird Party Advisory | |
| https://trac.torproject.org/projects/tor/ticket/33129 | x_refsource_MISCIssue TrackingVendor Advisory | |
| https://www.hackerfactor.com/blog/index.php?/archives/868-Deanonymizing-Tor-Circuits.html | x_refsource_MISCExploitMitigationTechnical DescriptionThird Party Advisory |
Change history (0)
No recorded changes yet.