Cisco ASA uRFP Bypass Vulnerability (Cisco-SA-20150812-CVE-2015-4321)

# Copyright (C) 2015 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("1.3.6.1.4.1.25623.1.0.106037");
  script_version("2022-02-09T09:27:46+0000");
  script_tag(name:"last_modification", value:"2022-02-09 09:27:46 +0000 (Wed, 09 Feb 2022)");
  script_tag(name:"creation_date", value:"2015-08-22 13:45:14 +0200 (Sat, 22 Aug 2015)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:P/I:N/A:N");

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

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

  script_cve_id("CVE-2015-4321");

  script_name("Cisco ASA uRFP Bypass Vulnerability (Cisco-SA-20150812-CVE-2015-4321)");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2015 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:"Cisco ASA is prone to a Unicast Reverse Path Forwarding Bypass
  vulnerability.");

  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 incorrect uRPF validation where IP
  packets from an outside interface, whose IP address is both in the ASA routing table and
  associated with an internal interface, are not dropped. An unauthenticated, remote attacker could
  exploit this vulnerability by sending spoofed IP packets to a targeted ASA in a subnet range that
  should be dropped.");

  script_tag(name:"impact", value:"An exploit could allow the attacker to bypass uRPF validation on
  the ASA which would cause packets to be incorrectly forwarded on the internal network.");

  script_tag(name:"affected", value:"Cisco ASA version 9.3 and 9.4.");

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

  script_xref(name:"URL", value:"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/Cisco-SA-20150812-CVE-2015-4321");

  exit(0);
}

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

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

if (version_in_range_exclusive(version: version, test_version_lo: "9.3", test_version_up: "9.4.1.103")) {
  report = report_fixed_ver(installed_version: version, fixed_version: "9.4(1.103)");
  security_message(port: 0, data: report);
  exit(0);
}

exit(99);