FreeBSD : OpenVPN -- out-of-bounds write in legacy key-method 1 (3dd6ccf4-a3c6-11e7-a52e-0800279f2ff8)

high Nessus Plugin ID 103523

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Synopsis

The remote FreeBSD host is missing one or more security-related updates.

Description

Steffan Karger reports :

The bounds check in read_key() was performed after using the value, instead of before. If 'key-method 1' is used, this allowed an attacker to send a malformed packet to trigger a stack-based buffer overflow. [...]

Note that 'key-method 1' has been replaced by 'key method 2' as the default in OpenVPN 2.0 (released on 2005-04-17), and explicitly deprecated in 2.4 and marked for removal in 2.5. This should limit the amount of users impacted by this issue.

Solution

Update the affected packages.

See Also

https://community.openvpn.net/openvpn/wiki/CVE-2017-12166

http://www.nessus.org/u?69492f87

http://www.nessus.org/u?84a97235

Plugin Details

Severity: High

ID: 103523

File Name: freebsd_pkg_3dd6ccf4a3c611e7a52e0800279f2ff8.nasl

Version: 3.8

Type: local

Published: 9/28/2017

Updated: 1/4/2021

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Medium

Base Score: 6.8

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

CVSS v3

Risk Factor: High

Base Score: 8.1

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

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

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

Patch Publication Date: 9/27/2017

Vulnerability Publication Date: 9/21/2017

Reference Information

CVE: CVE-2017-12166

IAVA: 2017-A-0285