OpenVPN 2.4.x < 2.4.6 Denial of Service Vulnerability (Windows)

#
# (C) Tenable Network Security, Inc.
#
include("compat.inc");

if (description)
{
  script_id(125263);
  script_version("1.4");
  script_cvs_date("Date: 2019/10/30 13:24:47");

  script_cve_id("CVE-2018-9336");

  script_name(english:"OpenVPN 2.4.x < 2.4.6 Denial of Service Vulnerability (Windows)");
  script_summary(english:"Checks the version of OpenVPN.");

  script_set_attribute(attribute:"synopsis", value:
"An application on the remote Windows host is affected by a denial of service vulnerability.");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version number, the version of OpenVPN installed on the remote Windows host is affected
by a denial of service (DoS) vulnerability in its interactive service helper component due to an invalid level of 
validation for incoming requests. An unauthenticated, local attacker can exploit this issue, by sending malformed 
requests, to cause the application to stop responding.");
  # https://community.openvpn.net/openvpn/wiki/ChangesInOpenvpn24
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d07ec3ea");
  script_set_attribute(attribute:"solution", value:"Upgrade to OpenVPN 2.4.6 or later.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-9336");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  
  script_set_attribute(attribute:"vuln_publication_date", value:"2018/05/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/04/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/05/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:openvpn:openvpn");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("openvpn_server_installed.nbin");
  script_require_keys("installed_sw/OpenVPN Server");
  exit(0);
}

include('vcf.inc');

app_info = vcf::get_app_info(app:'OpenVPN Server');

constraints = [{'min_version': '2.4.0', 'fixed_version': '2.4.6'}];
vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_WARNING);