Vulnerability in Openvpn

CVE-2005-2531

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 · last modified .

CVSS v2 metric

CVSS v2 base score 5.0 (Medium). Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P. This CVE predates CVSS v3 and has no v3 score from NVD.

EPSS exploit prediction

EPSS: 0.020 (79.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 80th percentile — 79.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2005-2531: held from 0.020 to 0.020.

EPSS over last 30 days · oldest: 0.020 · newest: 0.020 · change: 0.000

Affected products

  • Openvpn — versions 2.0, 2.0.1_rc1, 2.0.1_rc2

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2005-2531?
CVE-2005-2531 is a vulnerability in Openvpn. Published 2005-08-24.
Is CVE-2005-2531 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.