FreeBSD : openvpn -- denial of service: client certificate validation can disconnect unrelated clients (a51ad838-2077-48b2-a136-e888a7db5f8d)

medium Nessus Plugin ID 21488

Synopsis

The remote FreeBSD host is missing a security-related update.

Description

James Yonan reports :

DoS attack against server when run with 'verb 0' and without 'tls-auth'. If a client connection to the server fails certificate verification, the OpenSSL error queue is not properly flushed, which can result in another unrelated client instance on the server seeing the error and responding to it, resulting in disconnection of the unrelated client.

Solution

Update the affected package.

Plugin Details

Severity: Medium

ID: 21488

File Name: freebsd_pkg_a51ad838207748b2a136e888a7db5f8d.nasl

Version: 1.16

Type: local

Family: FreeBSD Local Security Checks

Published: 5/13/2006

Updated: 1/6/2021

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:openvpn, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Patch Publication Date: 8/19/2005

Vulnerability Publication Date: 8/3/2005

Reference Information

CVE: CVE-2005-2531

Detections

Analytics