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.

EPSS: 0.020 (78.3th percentile) — read the EPSS interpretation.

Affected products

  • Openvpn — versions 2.0, 2.0.1_rc1, 2.0.1_rc2
  • N/a — versions n/a

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.