Cisco ASA Software DHCP Relay Denial of Service Vulnerability (cisco-sa-20161005-asa-dhcp)

# Copyright (C) 2016 Greenbone Networks GmbH
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-or-later
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

CPE = "cpe:/a:cisco:asa";

if (description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.106341");
  script_version("2022-02-10T15:02:13+0000");
  script_tag(name:"last_modification", value:"2022-02-10 15:02:13 +0000 (Thu, 10 Feb 2022)");
  script_tag(name:"creation_date", value:"2016-10-06 12:09:26 +0700 (Thu, 06 Oct 2016)");
  script_tag(name:"cvss_base", value:"6.1");
  script_tag(name:"cvss_base_vector", value:"AV:A/AC:L/Au:N/C:N/I:N/A:C");
  script_tag(name:"severity_vector", value:"CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2018-10-30 16:27:00 +0000 (Tue, 30 Oct 2018)");

  script_cve_id("CVE-2016-6424");

  script_tag(name:"qod_type", value:"remote_banner");

  script_tag(name:"solution_type", value:"VendorFix");

  script_name("Cisco ASA Software DHCP Relay Denial of Service Vulnerability (cisco-sa-20161005-asa-dhcp)");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2016 Greenbone Networks GmbH");
  script_family("CISCO");
  script_dependencies("gb_cisco_asa_version.nasl", "gb_cisco_asa_version_snmp.nasl");
  script_mandatory_keys("cisco_asa/version");

  script_tag(name:"summary", value:"A vulnerability in the DHCP Relay feature of Cisco ASA Software
  could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition by
  causing an interface wedge.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");

  script_tag(name:"insight", value:"The vulnerability is due to improper handling of resources
  linked with the DHCP Relay feature. An attacker could exploit this vulnerability by sending DHCP
  packets at specific rates.");

  script_tag(name:"impact", value:"An exploit could allow an attacker to cause an interface to
  become wedged, and stop processing incoming traffic. Once this state is reached, restoration of
  service can only be achieved by reloading the device.");

  script_tag(name:"solution", value:"See the referenced vendor advisory for a solution.");

  script_xref(name:"URL", value:"http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161005-asa-dhcp");

  exit(0);
}

include("host_details.inc");
include("version_func.inc");

if( ! version = get_app_version( cpe:CPE, nofork:TRUE ) )
  exit( 0 );

check_vers = ereg_replace( pattern:"(\(|\))", string:version, replace:"." );
check_vers = ereg_replace( pattern:"\.$", string:check_vers, replace:"" );

affected = make_list(
  '8.4.7.29',
  '9.1.7.4' );

foreach af ( affected ) {
  if( check_vers == af ) {
    report = report_fixed_ver( installed_version:version, fixed_version:"See advisory" );
    security_message( port:0, data:report );
    exit( 0 );
  }
}

exit( 99 );