Cisco Network Convergence System 5500 Series Routers Local Denial of Service Vulnerability (cisco-sa-20170607-ncs)

# Copyright (C) 2017 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:/o:cisco:ios_xr";

if (description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.106857");
  script_version("2022-09-23T10:10:45+0000");
  script_tag(name:"last_modification", value:"2022-09-23 10:10:45 +0000 (Fri, 23 Sep 2022)");
  script_tag(name:"creation_date", value:"2017-06-08 11:35:21 +0700 (Thu, 08 Jun 2017)");
  script_tag(name:"cvss_base", value:"1.9");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:M/Au:N/C:N/I:N/A:P");
  script_tag(name:"severity_vector", value:"CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2019-10-03 00:03:00 +0000 (Thu, 03 Oct 2019)");

  script_cve_id("CVE-2017-6666");

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

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

  script_name("Cisco Network Convergence System 5500 Series Routers Local Denial of Service Vulnerability (cisco-sa-20170607-ncs)");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2017 Greenbone Networks GmbH");
  script_family("CISCO");
  script_dependencies("gb_cisco_ios_xr_consolidation.nasl");
  script_mandatory_keys("cisco/ios_xr/detected", "cisco/ios_xr/model");

  script_tag(name:"summary", value:"A vulnerability in the forwarding component of Cisco IOS XR
  Software for Cisco Network Convergence System (NCS) 5500 Series Routers could allow an
  authenticated, local attacker to cause the router to stop forwarding data traffic across Traffic
  Engineering tunnels, resulting in a denial of service (DoS) condition.");

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

  script_tag(name:"insight", value:"The vulnerability occurs because adjacency information for a
  Traffic Engineering tunnel's physical source interface is not propagated to hardware after
  the adjacency is lost. This information needs to be relearned. An attacker could exploit this
  vulnerability by logging in to the router's CLI with administrator privileges and issuing the
  clear arp-cache command.");

  script_tag(name:"impact", value:"A local attacker may cause a denial of service condition.");

  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-20170607-ncs");

  exit(0);
}

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

if (!model = get_kb_item("cisco/ios_xr/model"))
  exit(0);

if ("NCS-5500" >!< model)
  exit(99);

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

affected = make_list(
  '6.0.0',
  '6.0.1',
  '6.1.0',
  '6.1.1',
  '6.1.2',
  '6.1.3',
  '6.2.0',
  '6.2.1' );

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

exit(99);