tor: allows breaking its anonymity via single cell
Published Feb 20, 2009
5.1
MEDIUMCVSS 2.0
EPSS 2.12%
Description
Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) inserting, or (4) deleting a single cell, and then observing cell recognition errors at the exit router. NOTE: the vendor disputes the significance of this issue, noting that the product's design "accepted end-to-end correlation as an attack that is too expensive to solve."
Affected products
No data.
- ≤ 0.2.0.34
- 0.2.0.1
- 0.2.0.2
- 0.2.0.3
- 0.2.0.4
- 0.2.0.5
- 0.2.0.6
- 0.2.0.7
- 0.2.0.8
- 0.2.0.9
- 0.2.0.10
- 0.2.0.11
- 0.2.0.12
- 0.2.0.13
- 0.2.0.14
- 0.2.0.15
- 0.2.0.16
- 0.2.0.17
- 0.2.0.18
- 0.2.0.19
- 0.2.0.20
- 0.2.0.21
- 0.2.0.22
- 0.2.0.23
- 0.2.0.24
- 0.2.0.25
- 0.2.0.26
- 0.2.0.27
- 0.2.0.28
- 0.2.0.29
- 0.2.0.30
- 0.2.0.31
- 0.2.0.32
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.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:H/Au:N/C:P/I:P/A:P
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
2022-2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (15 key points)
Flat stretches are collapsed. Showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 2.12% (0.02117) | 81.19th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.12% (0.02117) | 79.37th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.53% (0.00527) | 65.16th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.85% (0.00855) | 82.96th | v3 (v2023.03.01) |
| May 24, 2024 | 0.51% (0.00506) | 76.44th | v3 (v2023.03.01) |
| May 10, 2024 | 0.42% (0.00422) | 74.11th | v3 (v2023.03.01) |
| Apr 25, 2024 | 0.34% (0.00344) | 71.23th | v3 (v2023.03.01) |
| Mar 15, 2024 | 0.31% (0.00311) | 69.39th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.28% (0.00284) | 67.79th | v3 (v2023.03.01) |
| Jul 10, 2023 | 0.85% (0.00855) | 79.99th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.60% (0.00604) | 75.22th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.14% (0.01136) | 59.45th | v2 (v2022.01.01) |
| Oct 18, 2022 | 1.14% (0.01136) | 58.28th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.14% (0.01136) | 56.27th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.14% (0.01136) | 34.23th | v2 (v2022.01.01) |
No CWE recorded.
References (7)
- http://blog.torproject.org/blog/one-cell-enough x_refsource_MISC
- http://www.blackhat.com/html/bh-dc-09/bh-dc-09-archives.html#Fu x_refsource_MISC
- http://www.blackhat.com/presentations/bh-dc-09/Fu/BlackHat-DC-09-Fu-Break-Tors-Anonymity.pdf x_refsource_MISCExploit
- https://access.redhat.com/security/cve/CVE-2009-0654 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=486706 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2009-0654
- https://www.cve.org/CVERecord?id=CVE-2009-0654
| Link | Providers | Tags |
|---|---|---|
| http://blog.torproject.org/blog/one-cell-enough | x_refsource_MISC | |
| http://www.blackhat.com/html/bh-dc-09/bh-dc-09-archives.html#Fu | x_refsource_MISC | |
| http://www.blackhat.com/presentations/bh-dc-09/Fu/BlackHat-DC-09-Fu-Break-Tors-Anonymity.pdf | x_refsource_MISCExploit | |
| https://access.redhat.com/security/cve/CVE-2009-0654 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=486706 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2009-0654 | ||
| https://www.cve.org/CVERecord?id=CVE-2009-0654 |
Change history (0)
No recorded changes yet.