OpenVPN before 2.0.1, when running with "verb 0" and without TLS authentication, does not properly flush the OpenSSL error queue when a client fails certificate authentication to the server and causes the error to be processed by the wrong client, which allows remote attackers to cause a denial of service (client disconnection) via a large number of failed authentication attempts
Published Aug 24, 2005
5.0
MEDIUMCVSS 2.0
EPSS 1.97%
Description
OpenVPN before 2.0.1, when running with "verb 0" and without TLS authentication, does not properly flush the OpenSSL error queue when a client fails certificate authentication to the server and causes the error to be processed by the wrong client, which allows remote attackers to cause a denial of service (client disconnection) via a large number of failed authentication attempts.
Affected products
No data.
- 2.0
- 2.0.1_rc1
- 2.0.1_rc2
- 2.0.1_rc3
- 2.0.1_rc4
- 2.0.1_rc5
- 2.0.1_rc6
- 2.0.1_rc7
- 2.0_beta1
- 2.0_beta2
- 2.0_beta3
- 2.0_beta4
- 2.0_beta5
- 2.0_beta6
- 2.0_beta7
- 2.0_beta8
- 2.0_beta9
- 2.0_beta10
- 2.0_beta11
- 2.0_beta12
- 2.0_beta13
- 2.0_beta15
- 2.0_beta16
- 2.0_beta17
- 2.0_beta18
- 2.0_beta19
- 2.0_beta20
- 2.0_beta28
- 2.0_rc1
- 2.0_rc2
- 2.0_rc3
- 2.0_rc4
- 2.0_rc5
- 2.0_rc6
- 2.0_rc7
- 2.0_rc8
- 2.0_rc9
- 2.0_rc10
- 2.0_rc11
- 2.0_rc12
- 2.0_rc13
- 2.0_rc14
- 2.0_rc15
- 2.0_rc16
- 2.0_rc17
- 2.0_rc18
- 2.0_rc19
- 2.0_rc20
- 2.0_rc21
- 2.0_test1
- 2.0_test2
- 2.0_test3
- 2.0_test5
- 2.0_test6
- 2.0_test7
- 2.0_test8
- 2.0_test9
- 2.0_test10
- 2.0_test11
- 2.0_test12
- 2.0_test14
- 2.0_test15
- 2.0_test16
- 2.0_test17
- 2.0_test18
- 2.0_test19
- 2.0_test20
- 2.0_test21
- 2.0_test22
- 2.0_test23
- 2.0_test24
- 2.0_test26
- 2.0_test27
- 2.0_test29
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:L/Au:N/C:N/I:N/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 1, 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 (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.97% (0.01966) | 79.64th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.97% (0.01966) | 77.71th | v5 (v2026.06.15) |
| Mar 17, 2025 | 1.41% (0.01410) | 79.18th | v4 (v2025.03.14) |
| Dec 12, 2024 | 2.42% (0.02416) | 90.33th | v3 (v2023.03.01) |
| Mar 7, 2023 | 3.36% (0.03363) | 89.88th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.32% (0.01319) | 71.27th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.32% (0.01319) | 71.23th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.32% (0.01319) | 69.22th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.32% (0.01319) | 44.98th | v2 (v2022.01.01) |
No CWE recorded.
References (7)
- http://openvpn.net/changelog.html x_refsource_CONFIRM
- http://secunia.com/advisories/16463 third-party-advisoryx_refsource_SECUNIA
- http://secunia.com/advisories/17103 third-party-advisoryx_refsource_SECUNIA
- http://www.debian.org/security/2005/dsa-851 vendor-advisoryx_refsource_DEBIAN
- http://www.mandriva.com/security/advisories?name=MDKSA-2005:145 vendor-advisoryx_refsource_MANDRIVAPatchVendor Advisory
- http://www.novell.com/linux/security/advisories/2005_20_sr.html vendor-advisoryx_refsource_SUSE
- http://www.securityfocus.com/bid/14605 vdb-entryx_refsource_BID
| Link | Providers | Tags |
|---|---|---|
| http://openvpn.net/changelog.html | x_refsource_CONFIRM | |
| http://secunia.com/advisories/16463 | third-party-advisoryx_refsource_SECUNIA | |
| http://secunia.com/advisories/17103 | third-party-advisoryx_refsource_SECUNIA | |
| http://www.debian.org/security/2005/dsa-851 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.mandriva.com/security/advisories?name=MDKSA-2005:145 | vendor-advisoryx_refsource_MANDRIVAPatchVendor Advisory | |
| http://www.novell.com/linux/security/advisories/2005_20_sr.html | vendor-advisoryx_refsource_SUSE | |
| http://www.securityfocus.com/bid/14605 | vdb-entryx_refsource_BID |
Change history (0)
No recorded changes yet.